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How do I know what size radiator I need?

Size – The size of your room drastically affects the size of your required radiator. A small radiator will struggle to heat a large room effectively because of the amount of air they are able to act against. This may result in an unbalanced room temperature and long-term energy wastage.

Large radiators will be able to quickly alter the temperature of a small room, however can be more expensive to run. Getting the exact size is important. To work out your room’s floor area you need to measure and multiply the floor length by its width. For example, a room which is 4 meters long and 3.5 meters wide has an area of 14 square meters.

To heat this room effectively you would need the correct size radiator model with a minimum wattage of 1430 watts. Heater Shop’s provides the most suitable radiator wattage for your room size; it forecasts the model’s ability to obtain and maintain an ambient temperature of 21°C.

What size radiator do I need for my PC?

The 120mm per Component Rule – A common rule of thumb that has been passed around the online forums is that you should dedicate 120mm (or 140mm) of radiator space per component that is to be cooled, with an additional 120mm (or 140mm) of radiator space if you are going to be overclocking.

1. Following this rule means that you’d have to dedicate 240mm of radiator space to a single overclocked component (which you can see in the picture above), 360mm of radiator space for two overclocked components (as you can see in the build below), and so on.
2. While this rule generally holds true and helps to minimize some confusion for beginners, not every chassis allows you to follow this rule without modification.

The sweet spot for CPU & GPU Loop is one 360mm radiator for three 120mm fans. (ANVIL build by Chris Stolze)

Which radiator for room size?

Single or double panel – If you already have a single-panel radiator, you can opt for a double-panel radiator if you are happy with the size of the radiator requiring an extra bit of heat. A double-panel radiator will provide any room with a higher heat output due to its bigger surface area and are ideal if you have larger rooms. Meanwhile, a single-panel radiator is great for smaller rooms.

Does a bigger radiator give more heat?

Yes. The heat output provided by a radiator depends on several different design aspects, including construction material and size. Generally, larger radiators will deliver a greater BTU output as they feature a bigger heat emitting surface area. Similarly, double panel radiators will offer a stronger heat output than a single panel radiator of the same length.

What happens if a radiator is too big?

When choosing a radiator to be installed in a room, it’s very important that you choose the right size. Too small and the rad might struggle to heat the room to a comfortable temperature. Too large and you might overheat the room and risk unnecessarily large heating bills, so it’s worth taking the time to get the size of you radiator correct.

Can a radiator be too large?

Posted on 05.02.2017 | Updated on 18.04.2017 | Radiators have several crucial characteristics. The most important of which – and don’t let anyone tell you otherwise – is size. When choosing, buying and fitting radiators, their size should be your first consideration. There are many factors involved in choosing radiators – style, material and compatibility with your heating supply being important ones.

• But these are all useless until you’ve measured the areas you want your radiators to heat and worked out what size radiator you need.
• Radiators and Heating Efficiency Getting the balance right with radiator size is critical.
• If your radiator’s too big, you’ll be wasting energy every time it’s on – and you may be taking up unnecessary wall space.

Then again, if your radiator’s too small, you’ll never get the heat output you need to get the temperature you want in the space. Meanwhile, your boiler will never be off, creating extra wear and tear on it – which won’t save you any money in the long run either.

• Fortunately there’s a simple calculation, which can ensure you get the right sized radiators for your home.
• BTUs and Radiators A radiator’s output is measured in British Thermal Units, more commonly referred to as BTUs.
• The higher the BTU rating of a radiator, the more heat output it will generate.
• Working out the BTU value you need from your radiators is a relatively simple calculation.

Rooms with more doors and windows (especially single glazed ones) will need radiators with a higher BTU value than those without. A simple calculation you can do though is to calculate the room’s volume (height x length x width, in metres) and multiply the result by 153.

• This will give you a rough idea of the BTUs per hour needed to heat it.
• To convert this to Watts, multiply the figure by 0.2931.
• Do the Maths – Then Choose Your Radiators Obviously it’s unlikely that you’ll find any radiators that match your BTU requirements exactly – but you can round up or down to find a close enough match.

Once you’ve done the calculations and worked out what size you need you can start looking at the other features you need from your radiators. There’s a wide enough range out there – so do the calculations and start choosing your radiators. Find Radiators that Fit Your Home Simply Radiators is a specialist in a vast range of radiators and designer heating products.

Is 120mm radiator enough for CPU?

I’d been looking forward to a group test of 120mm AIO liquid coolers for a while. I’d heard plenty of comments online about them being pointless compared with larger models with bigger radiators, but what surprised me was testing NZXT’s Kraken 120 when Intel launched its 12th-gen CPUs recently.

It actually managed to tame the mighty Core i9-12900K at stock speed, which is significant news for small form factor systems. It means that while many small or low-profile air coolers would struggle, using a 120mm AIO liquid cooler could be sufficient and would also dump the heat straight out of your case via the radiator.

These coolers are cheaper than larger models and easy to install, especially in cases with limited cooler height limits. There is a flip side to these positives, though, which relates to radiator size. The key benefit of larger radiators – and this applies to custom liquid cooling too – is that they have a much greater ability to dissipate heat.

This is due to their larger heatsink surface area and greater number of fans, which combine to offer better cooling at lower noise levels, as the fans don’t need to spin as fast to offer similar or better cooling. In addition, there’s more coolant in the loop, as radiators have large cavities for it to flow through them.

The high heat capacity of coolants means they can absorb a lot of heat before they actually warm up – the more coolant in the loop, the longer it takes before the fans need to spin up. As a result, larger AIO liquid coolers will remain quieter for longer.

Do thicker radiators cool better?

Materials – Yes, we’re going to go over materials again. It’s important. Just like other water cooling parts, radiators are made with different materials across different brands and models. While aluminum radiators are available and effective, they should only be used in a water cooling loop with all aluminum components.

1. The single exception to this is zinc-alloy radiators.
2. These radiators are designed for use in a mixed-metal system, but the zinc acts as a sacrificial annode.
3. It will corrode over time – how long depends on the process used to manufacture it.
4. Today’s water cooling radiators are typically made with copper, brass and aluminum.

The chambers at the ends of the radiator are usually brass, though copper isn’t uncommon and a few are or, The cooling fins will be copper or aluminum. This is one of the few places that aluminum is acceptable in your water cooling loop, since the fins are never in contact with the coolant.

Copper and brass work well together, and the two plastics used don’t react with any metals so corrosion isn’t an issue. None of the other materials offer the thermal transfer performance that copper does but they’re less expensive and allow the manufacturers who use them to offer these products at a lower price.

Given how small the tanks are, any impact on performance will be minimal.

1. 
2. Three common sizes of PC cooling radiators: 360mm, 240mm and 120mm.
3. Size

Size is a simple factor but in the case of a PC radiator it has a couple of different implications. The first is fit. Will the radiator physically fit inside your PC case? Can you mount it in the spot and orientation you want? The first number you’ll always see when you’re looking at a radiator’s size isn’t its length, width or thickness.

• It’s the sum total of fans that it was designed to work with along one side of the radiator.
• For example, a 360mm radiator is designed to work with three along 1 side (3 x 120 = 360), and a 280mm radiator is designed to work with two along 1 side (2 x 140 = 280).
• Less commonly, you may also see a shown as 120.3, or a 280mm radiator sown as 140.2.

This overall total fan size number won’t always tell you if a given radiator will fit in your PC case though. Not long ago you could safely assume that a PC case that advertised being able to house a 360mm radiator would house any 360mm case on the market. Alphacool’s 1080mm Nova radiator – not for the SFF crowd. Just about all radiator manufacturers will list the actual dimensions of their product: length, width and thickness. Those are the numbers that have to be used to check to see if a radiator you’re considering will fit in a given space.

• Many PC case makers will offer the radiator space limitations in their product info, but not all them.
• Manual measurement is best anyway.
• When you’re planning out your radiator placement and measurements, don’t forget to include the thickness of the fans that you plan to use with it.
• Many less experienced builders have made that mistake and ended up having to modify their plans.

Port / Flow Orientation – Dual pass vs Crossflow F or purposes of this article, the term ” end” refers to the ends of the radiator where the tanks are installed, “Side” refers to the solid sides of the cooling core between the tanks. Dual-Pass The standard PC radiator is known as a dual-pass radiator. Flow pattern of a dual-pass radiator, Coolant enters and exits from the same end of the radiator. To achieve this, the tank on the input/output end will be divided in two. On some radiators this is visible as a deep V shape in the middle, forming two completely separate tanks. The inlet and outlet tanks on this dual-pass radiator are clearly separated. Not all dual-pass radiators have this V shape though – some have what appears to be a single tank on the end. These tanks will have a dividing panel installed inside, creating two separate tanks.

1. The tank end opposite the input/output end of a dual-pass radiator is typically smaller than the split tank also, since it only serves to direct the coolant flow back to the end it came from.
2. Dual-flow radiators typically offer only two ports, but some models may have four or even six available on the input/output end, and a few even have a single port on the other end to allow for draining the radiator.

In the image below you can see the inner workings of a typical dual-pass radiator. I’d like to personally thank this little EK Coolstream Classic SE 120 for donating its body to science. A dissected dual-pass radiator, Note the plate welded to the inside of the upper tank, separating it into two, Crossflow Crossflow radiators are single-pass radiators. Instead of dividing the cooling tubes in half and sending the coolant on a round trip back to the end it started at, crossflow radiators split the coolant flow to all the cooling tubes immediately and send it on a one-way path to the other end. Flow pattern of a crossflow radiator, Coolant enters one end of the radiator and exits the other end, Crossflow radiators will always have ports on both ends. Like dual-pass radiators, some may offer more than two but they will always be present on both ends of the radiator.

Two different types of multiport crossflow radiators, Care must be taken with input and output on the first style. The end tanks on crossflow radiators are normally the same size on both ends. This will typically make it longer than an equivalent dual-pass radiator, making measurement of the actual radiator even more important.

The construction of a crossflow radiators means that coolant will flow from any port to any other port. There are no closed areas inside. That makes the choice of ports to use for intake and output very important, as that’s what controls the amount of coolant that’s actually flowing through the tubes and shedding its heat.

• Flow directions and cooling results from different inlet and outlet positions on a multiport crossflow radiator,
• Intake and outflow ports should be on opposite ends and opposite sides of any crossflow radiator.
• Which is better?

When you compare crossflow and dual-pass radiators, remember that they all use the same cooling cores. These tube-and fin cores are used to construct both types – the only difference in construction are the end tanks. has shown that when all other factors are equal there is a slight performance advantage on the part of the dual-pass radiator, which is why most radiators on the market are made in this style.

1. Cooling Capacity
2. There are a lot of things that determine the overall cooling capacity of a radiator – some of which don’t even involve the radiator itself.
3. Size

Like any air cooler, the cooling surface area of a radiator has more effect on its cooling capacity than anything else. Typical wisdom says to allow 120mm of radiator space per component being cooled plus another 120mm. This rule of thumb is honestly outdated as some of today’s hardware puts out more heat than any components did when the rule was made, but it’s a start.

Consider this a minimum. Remember also that the commonly-referenced fan size measurement only describes two dimensions in a radiator’s size. Thickness is important also. Thickness Logic says that a thicker radiator will perform better than a thinner one, simply because of the increased surface area. While that’s true in general, to enjoy the full benefits of a thicker radiator you have to be able to get air flow across the whole thing.

That typically means more fans, higher-pressure fans or faster fans – all which can add up to more noise.

• Material s
• Differences in materials used won’t affect the overall cooling capacity of a radiator by enough to measure without very sensitive instruments so we won’t take that into consideration.
• Fin Density

Fin density is a measurement of how many cooling fins a radiator has in a given space, usually measured in FPI or Fins Per Inch. The denser the fins the better it will cool but the more air flow it will take due to smaller passages between fins. This has to be handled with fan selection just like a thicker radiator.

1. Differences in fin density.
2. The left radiator has 18 fins per inch, while the right has 8,
3. Note that damage to fins like seen on the right will have virtually no effect on your r adiator’s performance.
4. Flow Rate The rate at which your cooling fluid moves through the radiator will affect its cooling ability.

Flow rate is a function of the restriction of the radiator and the performance of your, I won’t get into flow rates and head pressure here – look for a Components post on pumps in the near future, we’ll cover all that there. A note on the numbers : Some manufacturers will list cooling capacity figures for their radiators, calculated in watts.

These numbers are irrelevant to your cooling system, so use them only to compare theoretical capacities with other radiators from the same manufacturer. For example, if they offer two versions of 240mm radiator, you might use these numbers to know that one offers more cooling capacity than the other.

Anything beyond that is guesswork. Features While I’ve mentioned them previously, it’s worth listing some features you might want to look for in your next radiator. • Drain port – This is simply an additional port on the end of the radiator opposite the inlet/outlet ports.It makes draining the radiator (and possibly the entire water cooling loop depending on where it’s placed) easier to drain.

1. A screw shield on this radiator prevents accidental damage to the cooling core when installing fans.
2. • RGB – The RGB trend has found its way to radiators, with models available with backlit logos and even RGB strips that cover the full side of the radiator.
3. RGB lighting is finding its way into everything PC related – even radiators.
4. • Monitors – A few radiators are available with built-in OLED displays and temperature sensors.
5. Aesthetics

This is another area that’s changed fairly recently. Radiators used to be the barest and most boring-looking part of your PC. They all looked very much the same – black. A few were offered in white but that was all.

• Today you can not only buy radiators in a range of colors, but some even have replaceable colored side plates so you can change your colors if you want.
• BarrowCH Chameleon Fish radiator with interchangeable anodized aluminum side panels and integrated OLED temperature display.
• Fact vs Fiction
• You may have heard some commonly-circulated “facts” about water-cooling radiators.
• ” Thicker radiators cool better. ”
• ” A high fin count makes a system loud. ”
• ” A push/pull fan setup is best. ”
• ” Always put your radiators at the top of your case because heat rises. ”
• The first three statements above are true in certain circumstances,

Thicker radiators cool better if they have enough air flow. Between a thick and thin radiator with low to moderate but equal air flow the thinner radiator will very likely perform better. A high fin count can make a cooling setup loud if the air flow is high enough.

• High fin counts make for more effective cooling through increased surface area but they need more air flow to overcome the restriction caused by the high fin count.
• Depending on your fans, that air flow can be loud if it’s high enough.
• A push/pull setup is sometimes the best way to go.
• Using fans on both sides of the radiator is fine but if your radiator is cooling as well as it possibly can with fans on only one side, doubling your fan count is only going to cost more money and make the whole setup louder.

Heat rises by convection. It’s a force of nature, but it’s a very weak force. The slightest bit of mechanical forced air movement will overcome convection without measurable effort. In other words, convection is meaningless the second you install a fan and turn it on.

• Put your radiators where they can get adequate air flow in and out.
• How do I decide? With all these factors individually and all the permutations possible with them in combination, how do you decide what to get? The first step to that is deciding on what you want.
• Since aesthetics are too subjective for me to even comment on, let’s look at the other two reasons people get into water cooling: performance and noise.

Are you after the absolute best cooling performance possible without concern for cost or noise? Cram as much radiator space into your PC as you can with high-speed fans on both sides of each and turn them all the way up. You can use as many as you want in an external setup.

1. Is silent cooling more your thing? Again, use as much radiator space as you can but make sure your radiators have a low FPI count and install low-speed high static pressure fans on one side only.
2. Turn your fans up to just below the noise level you want.
3. You can consider those two examples to be extremes of both reasons, but the logic works.

What you end up with will depend on other factors like your budget and compromises will likely have to be made in one area or the other. Knowing all the factors involved will help you keep those compromises to a minimum. Stay tuned to our Components Series for all the info you need on pumps to finish out your cooling equations.

How many watts can a 120mm radiator cool?

_NaZ Superclocked Member

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searching though the forum i found this interressting formula: (OC TDP/ stock TDP) = (OC multi/ stock multi) x (OC Bclk/ stock bclk) x (OC Vcore/ stock Vcore) 2 concerning this my cpu would creat ~270W of Heat at my desired clockspeed. knowing that I would want to know how much heat 1 120mm rad can get rid off. EVGA P55 FTW (657) – Core i7 860 @4ghz EVGA GTX 480 SC @850/1700/2000 – GeIL Black Dragon 2ghz Be Quiet Dark Power P7 Pro 1200W – Antec 1200 WD Velociraptor – Win7 nateman_doo Omnipotent Enthusiast

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Re:Radiator Rule of thumb 2010/06/26 05:34:07 (permalink) If your looking for ANY type of mathematical formula to calculate any type of heat dissipation, or quantum singularity, or space time continuum, PM lehpron YerBuddy Omnipotent Enthusiast

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Re:Radiator Rule of thumb 2010/06/26 08:05:32 (permalink) nateman_doo If your looking for ANY type of mathematical formula to calculate any type of heat dissipation, or quantum singularity, or space time continuum, PM lehpron +1000 If anyone would have the formula he would. lehpron Regular Guy

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Re:Radiator Rule of thumb 2010/06/26 17:34:28 (permalink) _NaZ searching though the forum i found this interressting formula: (OC TDP/ stock TDP) = (OC multi/ stock multi) x (OC Bclk/ stock bclk) x (OC Vcore/ stock Vcore) 2 Yeah that’s my work there, specifically its an interpretation of Ohm’s law applicable to computer processor power and heat variances.

• The only truly unknown quantity is stock TDP.
• With that said, how did you estimate 270W, did you use the TDP rating for your CPU (95W) or estimate actual TDP? Intel’s ratings aren’t the real heat values of each CPU, they are just ranges a bunch of CPUs will fall under to make it easier to cooling companies to tailor heatisinks towards.

Frequency ratios affect each CPU core and coresponding Vcore, but you should add the tiny portion used by the integrated memory controller at least in the new Intel “Core i” CPU’s and AMD CPUs. Note however, Vdimm affects the RAM’s heat, not the CPU’s heat.

For LGA1156 CPUs, the PCIe controller is also in the CPU, so consider that extra heat. “Affect” is a certainty, it will happen; whether you can measure by thermal probe or sensor it is a different story. _NaZ knowing that I would want to know how much heat 1 120mm rad can get rid off. i know one rad isnt enough.

is there some kind of “rule of thumb” how much heat a rad can roughly handle ? Any single 120mm radiator is actually capable of removing more than 200W of heat by itself, but this is a design limit and the heat isn’t removed at any particular stable temperature that suits us, which varies person.

• More than likely heat removed at a design limit is at a temperature we as overclockers and enthusiasts aren’t comfortable with, hence needing more radiators to compensate.
• How many more depends on you, rule of thumb is generally perogative but IMO there is no such thing as overkill provided you did your homework, you already know what you want and whether what you get will work for you, for the most part.

Choose a minimum of 2-3 ratio gap, take your requirements, multiply by 2 or 3 and get radiators for that new value. It is safer to have a larger gap that way you aren’t at the mercy of ambient/case temperatures, fan CFM or pump flow rate varations which will force wildly varying load temperatures.

• Since load temps are everything to a stable overclock, it is best to plan ahead with more.
• All the components in your liquid loop absorb some heat and dump the rest, this is how all coolers work actually, when an object absorbs heat, its own temperature rises.
• All components have a thermal resistence factor, its basically a percent of what is absorbed.

Lower the better, but can’t go below zero. For example, a typical high-end air cooler can have a factor of 0.15 o C/W (degrees centigrade per Watt of heat) up to about a 210W load (which is about what six 6mm heatpipes can handle by themselves), this means for a 200W load, 15% will raise temps above ambient and you get load temps, or about 30 o C above.

A typical high-end liquid can get as low as a factor of 0.08 o C/W up to as much heat removal as radiators available. I’ll use Swiftech’s radiators to estimate, as they are the only vendor I know that gives detailed specs of their stuff away. The thermal resistence factor of their MCR120, MCR220 and MCR320 radiators at a flow rate of 2gal/min and 80CFM fans are 0.055 o C/W, 0.033 o C/W and 0.025 o C/W respectively (to get the total factor for the loop, add in the factor for the water block).

Their total amounts of heat removal under the same conditions are 175W, 325W and 450W, respectively. Doesn’t seem like much, I think those by HWlabs are able to handle twice the load. But then we are talking about a flow rate of 2gal/min, doubling that will give you results by deminishing returns. When plotting these on a graph, you’ll see with evey additional radiator, the thermal resistence drops exponentially while the heat removal curve looks almost straight, as expected though after a few dozen it could level out: Depending on which brand of rads you go with, the amplitude of the plots will change, but the curves will have the same form. I threw in those formulas so you can make your own estimatations, but I’m sure some may regard that I had too much fun with this post. quadlatte CLASSIFIED ULTRA Member

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Re:Radiator Rule of thumb 2010/06/26 21:00:21 (permalink) you the man lehpron nateman_doo Omnipotent Enthusiast

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Re:Radiator Rule of thumb 2010/06/26 21:23:21 (permalink) Regular Guy my a$$, that man is as close to Albert Einstein as we get here in these forums. quadlatte CLASSIFIED ULTRA Member

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Re:Radiator Rule of thumb 2010/06/26 23:55:02 (permalink) nateman_doo Regular Guy my a$$, that man is as close to Albert Einstein as we get here in these forums. someday we may see his smiling face on a science mag with evga shirt YerBuddy Omnipotent Enthusiast

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Re:Radiator Rule of thumb 2010/06/27 00:37:50 (permalink) lehpron,rule of thumb is generally perogative but IMO there is no such thing as overkill provided you did your homework. That, I can understand! Hooray! Most of the time lehpron you go way over my head. Not that it’s hard to do. I’m just glad that you are in these forums. Johnny-1987 iCX Member

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Re:Radiator Rule of thumb 2010/06/27 02:21:22 (permalink) nateman_doo Regular Guy my a$$, that man is as close to Albert Einstein as we get here in these forums. lol +1, i could hardly understand he said Core i7-975 / 3x2GB 1866mhz Dominator Gt’s / EX58-UD3R / SLI GTX 295 Co-ops / 2x 128gb SSD’s / Corsair HX-1000W / Heatkiller Water Block 7/16 Primochill U/V Tubing 360GTX Black ice rad/ PA 120.3 D5-Vario Pump EK-Multioption 250 Rev Reservoir Primochill Non-Conductive Coolant 1/2 DD fatboy Fittings lehpron Regular Guy

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Re:Radiator Rule of thumb 2010/06/27 15:28:50 (permalink) I can’t tell if you guys are making fun of me or putting yourself down, just ask questions, don’t hesitate, anything. But you have to do it, I can’t initiate as I can’t read minds. _NAZ, when you get back in here I’d like to know your stock Vcore, I’m still have a hard time with how you figured your 860 to be dissipating 270 Watts, seems almost double what it could be. Going by the formula: (OC TDP÷stock TDP) = (19÷21) x (200÷133) x (1.3÷stock Vcore) 2 if assuming 95W TDP as your stock (which it isn’t btw), and 270 for the OC TDP, then your stock Vcore was way down at 0.89v.

• This was done by taking 270÷95 = 2.84, then divide the multi ratio and divide the bclk ratio, then take the square root.
• Lastly, divide 1.3 from this number and you get the value for stock Vcore.
• When you do the TDP equation, do the division first, then raise the voltage exponent, them multiply everything together.

Fact is, the typical i7 CPU will have a stock value between 1.1 and 1.3, OC TDP will not be higher than 160W at your settings for 3.8GHz – you could use an H50 with two high-flow fans and call it a day. The impact of hyperthreading according to many reviews have shown that enabling it increases temperature by 5%; all things equal, this accounts for a 5% increase in heat wattage.

As for estimating 860’s TDP, I set the fastest of a series/type as the hottest part and scale down by clockspeed (or process tech or cache). There is an i7 880 rumored to appear, so I’ll tentatively assume 880 is 95W TDP to qualify for the rating.860 has the 21x stock multi, 880 is supposed to get the 23x stock multi, so 860 is 9% slower.

Assuming the same, or very similar stock voltage, then that’s 9% less heat, or about 86W – this is closer to true i7 860 stock heat load. Redoing the OC TDP equation and using this review’s reference stock Vcore (since I don’t know yours): (19÷21) x (200÷133) x (1.3÷ 1.247) 2 = 1.478 86W x 1.478 = 127W – this is closer to your heat load, not 270.

Above I stated best to have a gap between what you need and what you have, don’t get minimum. So multiplied by 2 or 3 and we get a radiator set from 260 – 390W, any dual 120 radiator will suffice, more than that will bring temperatures lower but with diminishing returns. If you pruchased those dual rads from Swiftech, MCR220, that’s a thermal resistence factor of 0.033 o C/W supporting 325W at 2gal/min and a pair of 80CFM fans.

A 2gal/min pump is a their 350/355 pump and if you choose Swiftech’s Apogee GT CPU block which is rated for about 0.05 o C/W at 2 gal/min. Total thermal resistence factor is the sum, 0.05+0.033 = 0.083 o C/W, What does this mean and why should you care? At a load of 127W, a resistence of 0.083 o C/W means the cooler as a whole will raise temperatures by 127W x 0.083 o C/W = 10.5 o C above ambient.

Which ambient, air? Not necessarily, the liquid in the loop doesn’t act as just a medium, not all the heat is transfered from the block to the radiator, its the whole reason the liquid heats up. For Swiftech’s radiator tests, they maintained a 10 o C difference between air temeprature and the liquid temperature throughout.

So the 10.5 o C actually adds to the liquid temperature. Your theoretical minimum full load temperature with dual rads would then be 10 + 10.5 = 20.5 o C above the reference air temperature, which is the air entering the radiator (not air measured anywhere inside or outside your case or general room temperature).

1. If the air temperature entering your dual 120’s is 35 o C, then the CPU IHS full load temperatures could be 55.5 o C.
2. If you went for Swiftech’s triple 120 rad instead your full load temps dip into the upper 40’s.
3. Here’s another example: When K|ngp|n ran his QX6700 to a WR 4.9GHz back in 2006, I memorized his numbers: 15 multi from stock 10, 327Mhz FSB from stock 266, and Vcore of 1.792 from stock 1.25.

His full load temps were -191 o C centigrade, used LN 2, His TDP ratio was = (15÷10) x (327÷266) x (1.792÷1.25) 2 = 3.79 times higher than stock, or almost 500W of heat from a 65nm quad! LN 2 boils at -196 o C, so the thermal resistence of his copper pot was the change in temperature divide by heat wattage or (-196 – (-191))÷ ~500 = 0.01 o C/W. Superclocked Member

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Re:Radiator Rule of thumb 2010/06/27 16:04:20 (permalink) In almost any post regarding vcore, the wattage/TDP is increased by a factor of (current vcore/ stock vcore)². My question is why is it squared? My theory is that watts= Volts * amps so a 10% increase in vcore should result in a 10% watts, not 21%. lehpron Regular Guy

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Re:Radiator Rule of thumb 2010/06/27 19:26:10 (permalink) First, the power and heat may be measure in Watts, they aren’t the same number. The difference is energy efficiency, for electrical components, 80-85% of power input is heat dissipated. The remaining 10-15% of power in is used to run your programs, for instance.

1. Power is voltage times current (P=IV), but since voltage is current times resistence (V=IR), we can say voltage squared divided by resistence is also power (P=V 2 ÷R) – this is the definition of Ohm’s Law.
2. When we change the frequency of a processor, we mess with the inverse of the internal resistence of the circuit.

A process called electromigration is already occuring in many processors, that electrons leak out of the silicon at a predesigned steady rate that for a certain stock voltage, if the processor is kept at a certain temperature, it maintains a certain lifespan. CLASSIFIED Member

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Re:Radiator Rule of thumb 2010/06/27 21:52:39 (permalink) The power consumption of your CPU depends on its operation temperature. As the temperature of a transistor rises, so does its power consumption. So not only is your CPU running hotter, but it starts to use power power, which in turn heats it up even more. lehpron Regular Guy

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Re:Radiator Rule of thumb 2010/06/28 13:46:16 (permalink) The above TDP formula has no temperature factor, it is a plug’n chug manipulation based on numbers that may have been gathered at a certain temperature. Only if a series of points were plotted with variations in temperature would that trend point towards a variation in heat/power since circuit resistence is temperature dependent and thus the circuit would not need as much voltage the lower those temperatures became.

This pretty much explains the advantages of better cooling from stock, whether overclocked or not. In effect, you’re right, if K|ngp|n’s QX6700 was stable 4.9GHz at any temperature, then the room temp Vcore would be much higher than 1.792v because this was the requirement at -191 o C, and thus the ambient heat dissipation would rise significantly.

If 2v was required at ambient, that’s a 25% increase from LN 2, But such speeds cannot be maintained at higher temperatures, so the only real way to detect variations in heat/power is if a colder cryogenic was used (like LHe 2 ) to see how much less Vcore was needed for the same clockspeed, since with LN 2 4.9Ghz was stable with 1.792v. Omnipotent Enthusiast

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Re:Radiator Rule of thumb 2010/07/04 05:53:41 (permalink) lehpron I can’t tell if you guys are making fun of me. Quite the contrary. Phoenixx45 CLASSIFIED Member

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Re:Radiator Rule of thumb 2010/07/04 06:43:58 (permalink) YerBuddy lehpron I can’t tell if you guys are making fun of me. Quite the contrary. +1 lehpron just ask questions, don’t hesitate, anything. But you have to do it, I can’t initiate as I can’t read minds. Teach me your ways White Widow – NZXT 810 Processor : Intel Core i7 2700 @ ? Memory : 8GB Corsair Dominator GT Hard Drive(s) : 1.2x 120Gb Vertex 2 SSD 2, Raptor 70GB 3. Raptor 300GB 4. Western Digital 1TB Video Card : 3 x EVGA GTX 480 w/ Back Plate & HF Bracket in SLI Sound Card : X-Fi Titanium Fatal1ty Champion Series Motherboard : EVGA z68 FTW _NaZ Superclocked Member

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Re:Radiator Rule of thumb 2010/07/04 10:56:55 (permalink) @ lehpron, thank you very much. those graphs where what i was looking for 😀 and yes, i had a bubu in my calculations. i forgat that 21 was the stock multiplier and not my current one ^^. also my desired clock is 4.2ghz. EVGA P55 FTW (657) – Core i7 860 @4ghz EVGA GTX 480 SC @850/1700/2000 – GeIL Black Dragon 2ghz Be Quiet Dark Power P7 Pro 1200W – Antec 1200 WD Velociraptor – Win7 RBIEZE CLASSIFIED Member

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Re:Radiator Rule of thumb 2010/07/04 11:20:15 (permalink) They say opposites attract. I hope you meet someone who is good-looking, intelligent, and cultured. http://www.youtube.com/watch?v=W2WsPN-rr9o Evga X58 4Way sli,W’Cooled i7 950 @3.8, Mushkin redline mem @6-7-6-18 1600Mhz, 2-Evga GTX770 Sli, Evga Gtx460 Physx, Corsair Neutron 120GB SSD,Samsung 240SSD, W.D Black 640GB /Corsair TX950 Psu, Hanns-G 28″ Lcd, Logitech G540 5.1 Surround My Affiliate Code: EECLVEDV7Z jayjose New Member

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Re:Radiator Rule of thumb 2010/10/15 21:08:32 (permalink) As I read along regarding liquid cooling and stumbled upon some of lehpron’s post, I just want to share this CPU wattage calculator that I found while googling (in pursuit to fully understand the content of this thread). tplague New Member

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Re:Radiator Rule of thumb 2010/10/15 22:56:53 (permalink) lephron you have my permission to date my mom. T-Plague whodaddy SSC Member

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Re:Radiator Rule of thumb 2010/10/16 05:30:04 (permalink) E-759 CLASSIFIED & I7 920 DO B261 OCZ DDR 3 1600 Gold 6GS / TFC 480 and TFC 360 w KOOLANCE RAD SUPPORT 2×655 PUMPS IN SERIES/ BITS 150Z RES EK FULL COVERAGE BLOCK / BITS COMPRESSION/ROTARY FITTINGS EK HF SUPREME PLEXI COPPER CPU BLOCK 1/2X5/8 TUBING 2x GTX 470 SC W EK BLOCKS/WD 150 RADPTOR WD 300 RAPTOR WD 1TB CORSAIR 800D CASE/CORSAIR HX-1000 http://www.heatware.com/eval.php?id=67849

Does radiator size matter?

It is vital to get the correct balance with the size of your radiators in relation to the heat output they offer. If your radiator is too big, it will minimize essential wall space and use excess energy whenever it is in operation. By contrast, if your radiator is too small, it won’t have the capacity to properly heat your space to the required temperature.

Are smaller radiators better?

Getting the balance right – If your perfect radiator is too small, it will struggle to warm the room as it won’t be able to produce enough heat. This will place extra strain on the boiler, while also increasing your heating bills as you keep your heating switched on for longer than necessary. So, you’ve picked out a beautiful new radiator, but is it the right size for your room?

Can a radiator be too big for room?

Working out radiator size – When replacing or adding radiators to your home it’s crucial that each room gets the right size radiator. A radiator that is not powerful enough will not be able to heat the room adequately, but a radiator that is too big will not only overheat the room but will cost you unnecessary money to run. A radiator’s size (or power) is measured in BTUs.

How do I know if my radiator is big enough?

What Size Radiator Do I Need? – The best way to figure out what size radiator you need is to use a BTU calculator to see how much heat your room requires. Once you have made this calculation, you can go ahead and choose a radiator size that caters for your requirements. Take a look at our BTU calculator here to get started – then come back to find out more!

Is bigger radiator size better?

Core Size – In the world of radiators, bigger is better. A larger surface area can dissipate more heat. You will need to measure your vehicle. For more cooling capacity, get the biggest radiator that will fit. (This may require some custom fabrication.)

Is it better to get a bigger radiator?

Radiator Size – Size is an extremely important aspect to consider when looking for the most efficient radiator. Installing radiators that are either too big or too small for the room can make it difficult to heat your home to the ideal temperature and can result in energy being wasted which will reduce its efficiency.

• You can calculate the size that your radiator should be by using the dimensions of the room and the style of windows.
• Typically, larger radiators are more efficient due to having a bigger surface area to radiate the heat from.
• This means that the water inside can be heated to a lower temperature than that inside a smaller radiator and still generate the same amount of heat.

However, selecting larger than necessary radiators can produce excess heat that ends up being wasted and decrease the level of efficiency.

How do I know if my radiator is too small for my room?

Use a BTU Calculator For Radiator Sizing – Radiator output is measured in BTUs, so you need to calculate the required BTU for each room in your home. The easiest way to check the radiator sizing for your home is to use a BTU calculator. BTU stands for British Thermal Unit and is a standard way to measure the heat output of a radiator. In mainland Europe, they use wattage but here in the UK, we like to be different, and both measurements are used. To use a BTU calculator, you will need the following information:

Width, height and length of each room in the home (in metres)Type of windows, single or double glazed etcThickness of the external walls; single or double skin etcInsulation between the two walls (cavity) and depth of insulation in the loftWhat is located below and above each room, i.e. another room, an attic or a concrete floor etc

Don’t worry if you don’t have all the details, just assume a worst-case scenario and the calculator will suggest a radiator size slightly larger than you need. While there are tons of BTU calculators on the web, we feel that this is the best one,

Can I replace a radiator with a bigger one?

If your small radiator is looking a little worn and tired and isn’t kicking out as much heat as you’d like, you might be wondering if you could replace it with a sleek new designer radiator without much effort. The answer is a resounding yes! The good news is that you won’t need to engage the services of a plumber or fork out money on expensive tools to do it either because it’s something that you and a friend can achieve quite easily with a few bits and pieces that many of us already have in our at home toolboxes.

Can a smaller radiator cause overheating?

Yes – a smaller radiator would have a tendency to create engine overheating.

How do I know if my radiator will fit?

Measuring your radiator – Frequently asked questions – You can measure radiator pipe centres by using a tape measure to work out the distance from the centre of the left hand pipe inlet to the middle of the right hand pipe inlet. For further information about home radiators and measuring up for their installation, take a look at our dedicated blog, How To Measure A Radiator,

• Simply put, you can work out radiator pipe centres by using a tape measure to record the distance from the centre of the left hand pipe inlet to the centre of the right hand pipe inlet.
• To find out more about home radiators and how to measure up for them, consult our dedicated blog, How To Measure A Radiator,

Wall to pipe centres provide a measurement of the distance between the wall and your radiator’s pipe inlets at the point they enter the radiator valves, In order to measure pipe centres, you will have to measure from the centre of the pipe inlet to the wall. John Klee With a background in sports journalism, John counts content writing amongst his key passions. He’s always peppering our Advice Centre feed with reasoned and researched home heating tips, and providing expert solutions to the questions you want answering. Fine football and music connoisseur. In his own head, at least.

Can a radiator be too big for room?

Working out radiator size – When replacing or adding radiators to your home it’s crucial that each room gets the right size radiator. A radiator that is not powerful enough will not be able to heat the room adequately, but a radiator that is too big will not only overheat the room but will cost you unnecessary money to run. A radiator’s size (or power) is measured in BTUs.

How do I know if my radiator is too small?

If your perfect radiator is too small, it will struggle to warm the room as it won’t be able to produce enough heat.

Is it better to get a bigger radiator?

Radiator Size – Size is an extremely important aspect to consider when looking for the most efficient radiator. Installing radiators that are either too big or too small for the room can make it difficult to heat your home to the ideal temperature and can result in energy being wasted which will reduce its efficiency.

1. You can calculate the size that your radiator should be by using the dimensions of the room and the style of windows.
2. Typically, larger radiators are more efficient due to having a bigger surface area to radiate the heat from.
3. This means that the water inside can be heated to a lower temperature than that inside a smaller radiator and still generate the same amount of heat.

However, selecting larger than necessary radiators can produce excess heat that ends up being wasted and decrease the level of efficiency.