Performance
Performance has been tested on the Intel Skylake-X platform which contains the i7-7900X processor and ASUS X299 TUF Mark 2 motherboard. Used RAM is Ballistix Elite 64GB DDR4-3000. All software tests were performed in Windows 10 x64 with the latest updates.
Custom cooling loop includes the Heatkiller IV CPU and GPU water blocks, dual 360mm radiators and six fans at about 800 RPM.
The Heatkiller IV really improves GPU temperature. Differences in our tests are showing at least 40°C difference between reference Nvidia cooler and the Heatkiller GPU water block. What more, difference between standard settings and overclocked at higher voltage are only 2°C! It clearly shows cooling potential.
Temperature is first limiting factor if we talk about GTX1080 Ti boost frequency and overclocking potential. On standard, FE Edition cooler we simply can’t overclock our graphics card without throttling and full load temperature without overclocking is close the throttling point which is 90°C. Because of the way how Nvidia Boost works, even if card is not overheating then we can see frequency drops as it adjusts GPU frequency depends on environment so temperature, power limit and voltages.
Below you can see typical frequency in our tests. Only cooler change gave us couple of MHz higher boost. Additionally card is keeping higher average frequency and there is no throttling under full load.
Maximum frequency after overclocking on standard cooler was about 2000MHz. However, typical frequency with often throttling was no higher than 1950MHz. The Heatkiller IV let our GTX1080 Ti fly above 2050MHz. Stable frequency seems about 2030-2050MHz with maximum boost up to 2100MHz. At the same time GPU temperature after overclocking is only 2°C higher. It looks great, especially that all is really quiet.
Below is one of the results with GPU-Z reading.
and some more tests in 3DMarks
There is clearly an improvement on better cooling but I won’t hide that we already reach the point where our graphics card is limited by power limit and voltage. Limits can be removed but it’s not easy on these cards.
The main difference which you will see or maybe hear is how quiet your PC become after moving to water cooling. It’s probably the best reason to get the Heatkiller IV for the GTX1080 Ti. I’m not even comparing noise level. I will only say 40°C difference. All who own FE version of GTX1080 Ti know what I mean. FE cooler barely meets Nvidia specification and it shouldn’t come with so expensive graphics card.
