Proof that a custom PC water-cooling loop can improve performance

Thermaltake Core P5
Thermaltake Core P5 (Image credit: Rich Edmonds / Windows Central)

Prior to carrying out our water-cooling project on the Core P5 case, we measured temperatures for the CPU and GPU to see just how good the case would be for airflow, with a single fan to cool everything down (excluding the fans on the GPU). We found the Cooler Master Hyper 212 Evo CPU cooler to perform wonderfully in keeping the overclocked Intel Core i5-6600K at a stable 126 degrees F (52 degrees C), running at just 675 RPM.

That said, 126 degrees F is still more than 100 degrees F, and we'd like to have it below that marker. The case makes things difficult when it comes to air-cooling a CPU, because there's next to no airflow inside the case. Any case fans that can be installed without modding simply blow air straight onto the glass panel and aren't efficient by any means. It's clear that this fact put the 212 Evo at a slight disadvantage, but 126 degrees F is still a good temperature and well within the operating range.

To serve as a reminder, here's what we installed:

We pushed the system to its limit for 45 minutes, which resulted in the following readings:

Swipe to scroll horizontally
ComponentMax temperatureMax fan speed
GPU140 degrees F (60 degrees C)1,090 RPM
CPU102 degrees F (39 degrees C)Pump: 2,067 RPM
Radiator Fans: 640 RPM

Ambient temperature was 72 degrees F (22 degrees C). Our lowest RPM reading for the pump was recorded at 1,724 RPM with idle on around 1,849 PRM. Radiator fans — four of them, and we used a 480mm radiator for the CPU alone — hit 640 RPM with idle at around 603 RPM. Turning all fans up to their max settings and letting the pump sound like a drill brought temperatures of the overclocked Core i5-6600K down to just 93 degrees F (34 degrees C).

The CPU was at 4.0GHz for testing, but we were able to push the CPU to 4.8GHz before the system became unstable. At this level, the highest temperature reading was 114 degrees F (46 degrees C). All-in-all, the loop was a success and it can comfortably handle the amount of heat being produced by the CPU.

In other words, we're very happy with the results.

Rich Edmonds
Senior Editor, PC Build

Rich Edmonds was formerly a Senior Editor of PC hardware at Windows Central, covering everything related to PC components and NAS. He's been involved in technology for more than a decade and knows a thing or two about the magic inside a PC chassis. You can follow him on Twitter at @RichEdmonds.

8 Comments
  • Super Duper that isn't sgs8mse related!
  • When the testing loops run for 1 hours on cpu intensive task like prime. This should tell you actual temps from copper and water difference. For example copper will heat quickly but also cool down this changes to water which heats slowly but retains heat more. So if your a cold boot system is saying 46*c but over the 1 hour it could be 50*c. Water cooling test reviews do not normally tell you this!
  • That title is wrong. It will not improve the performance. It will allow you to push the hardware to new limits that results in improved performance. There is a difference.
  • That`s actually no proof of anything.
    PC Cooling is more than just numbers. Water cooling is efficient at taking the heat from a component and throwing it out the case. Due to the water`s thermodynamic ability it means it will take a lot of time to get to it`s peak temperature, thus making the components run cooler but at the same time it takes the same amount of time to loose it. A simple copper cooler will reach the max temperature faster but it will also cool faster than a water cooling loop after the hard work/gaming has stopped. After messing with water coolers i can tell you that good large Air coolers are always better than water cooling solutions, this unless you want those high end GPUs to stay "frosty". If something goes wrong in a custom loop there are some catastrophic scenarios that might happen, in an Air cooler you just get an warmer device if the fan fails, plenty of time to stop everything. Also you don`t have to mess with buggy software to control everything... Did i mention money ? :)
  • Bad, misleading article. From the article it seems the thing to remember is watercooling is better than air cooling. The fact that it was a 4:1 setup was not explicitly mentioned. 4:1? The 212 has the cooling surface of 1x 120mm. The Radiator has 4x120mm cooling surface. So despite being 4 times larger (roughly) it only outperformed the air cooler by 13 degrees C. If you compared the Cooler Master 120mm tower with another high quality 120mm tower, you would also see a 13 deg. C or better temperature drop. And you would have lots of money left to spend on other stuff as well.   The article should read more like "High end water cooling beats stock coolers hands down."
  • "Turning all fans up to their max settings and letting the pump sound like a drill..." lol, no thanks. I'll run a little warmer.
  • Just do a mineral oil case in a fish tank. Super efficient at dispersing heat, my buddy make one and put in one of the scuba divers and the treasure chest, it was awesome. You just need to put rubber gaskets around the cables that do not go in the tank. Just search bing for "mineral oil PC."
  • You can achieve the same with All-In-One watercooling... no need to muck around with custom loops