Testing & Results
I tested the V8 GTS in both vertical and horizontal orientations, but it didn’t reveal any significant differences in load temperatures. Normally, the less the fluid in the heat-pipes have to deal with gravity as they condense and expand the greater potential you have for performance (see the previous page).
There are enough bends and curves in those heat-pipes that may be making it tough for gravity to have an advantage one way or the other, or perhaps the use of a horizontal vapor chamber moved the “bottleneck” for heat transfer away from the heat-pipes themselves.
In fact, in the horizontal orientation pictured above the temperatures were around .5C hotter. I’ll attribute that to poorer airflow, as the front-to-rear airflow in the NZXT H630 I used for testing is less obstructed than the bottom-to-top airflow, even with the addition of a 200mm exhaust fan – and even though the GPU wasn’t under load during the stability test, the horizontal orientation basically pulls air straight off of the GPU. The point I’m trying to make is this: find the orientation that works the best in your rig, as I can only give you the results I’ve found using my own equipment.
The CPU coolers were tested installed in a computer case in its normal orientation (a NZXT H630). A 200mm top/rear exhaust fan was added to the enclosure to aid in cooling VRMs and most of the front drive cages were removed to clear the path from the 200mm intake fan. The GPU remained installed during testing. All fans were set to 100% to remove that variable from the results (motherboard fan control was disabled). This is how I would assume most enthusiasts would set up a similar case while overclocking a similar platform.
All tests were performed using the AIDA64 Extreme Edition System Stability test using 100% fan settings on an Asus M5A99FX PRO R2.0. The test was allowed to run until temperatures plateaued, then I recorded the ambient temperature of the intake air and began logging temperatures over the next minute. After an initial warm-up run, I ran each test at least three times (more if I received inconsistent results), and recorded the ambient temperature again. Once I had “good data,” I dropped the best and worst results and subtracted the (average over the test) ambient temperature from the median result to arrive at the delta T temperature you see in the chart.
Each time a heat-sink was swapped, the Tuniq TX-2 thermal interface material I used for each application was cleaned off of the contact surfaces with Arctic Silver’s ArctiClean two-step TIM remover, and an appropriate amount of TX-2 replaced for the next heat-sink. Due to the nature of applying TIM and mating two surfaces, I would like to adopt a 3% margin of error – even though my thermometers and the built-in thermal diode measure temperatures down to one-tenth of a degree Celsius, it could be assumed that temperatures within a degree of each other are essentially the same result.
Motherboard: Asus M5A99FX-PRO R2.0 w/ 1708 BIOS/UEFI
System Memory: 8GB (2x4GB) GSkill Ares 1600MHz DDR3 CL8
Processor: AMD FX-8320 Piledriver, 4.6GHz/1.428V LLC (Extreme)
Video: Sapphire Radeon 7950 3GB 1000MHz Core, 1300MHz mem
Disk Drive 1: OCZ Vertex 2 240GB
Enclosure: NZXT H630, +200mm exhaust fan (top/rear)
PSU: Rosewill Lightning 800W Modular 80+ Gold
Monitor: 1920×1080 120Hz
Operating System: Windows 7 Ultimate 64-bit w/SP1
It’s at this point where I realized I didn’t know what I was expecting. Maybe I was caught up by the marketing, maybe I thought two 140mm fans would magically whisk all of the heat away, maybe I thought the price would place it along similar products (as has been my general experience in the past). Maybe I was expecting too much of the horizontal vapor chamber, or maybe I didn’t see the maximum benefit from it as the heat-spreader on the FX-8320 is pretty big (it might fare better on Socket 1155/1150 platforms). I don’t think any of these things impacted performance negatively, but I guess I was expecting more performance – especially for the price.
That pesky EVO 212 shows its value again, but remember I do not include noise results. I can definitely say the V8 GTS is much quieter at 100% RPM than the EVO, and the character of the noise is entirely different as well. Keep aspects like these in mind when looking at a data chart; it only displays one attribute of the product. While cooling performance/price is an important ratio, it isn’t the only part of a product that contributes to the final price. Weight, aesthetics, sound, mounting system, dimensions and clearances are all considerations as well.