Thermal Test Method
For thermal testing I decided to use a 5 mount method of logging temperatures at a fixed ambient measuring core, water, and air temperatures very carefully. Here are some of the specifics in my testing method:
- Intel i7 2600K Processor – Overclocked to 4800 MHz, 32nm, Vcore = 1.392 under load. Motherboard is an MSI P67A-GD65 with 8GB of Corsair Vengance memory. Everything else is on air at the moment. Test bench is a Danger Den Torture Rack
- 5 separate TIM applications and mounts, more if needed.
- Logging temperatures over a 45 minute test, 10 minute warmup is removed from the results, and the entire logged run is provided for review.
- Temperature Probes Deployed – I kept my sensors fairly basic, but I did run a few extra’s just for interesting information. This includes a sensor for:
- 2 ea Water sensors (After radiator and pump, just before CPU block) Dallas DS18B20 Digital one-wire sensors, and CrystalFontz CFA-633
- 4 ea Air In Dallas DS18B20 Digital one-wire sensors, and CrystalFontz CFA-633
- 4 ea i7 2600K DTS sensors these were logged using Real Temp 3.67 .
- Crystal Fontz logging is accomplished through the use of their Cyrstalfonts 633 WinTest b1.9. Only special settings are turning off all packet debugger check boxes to avoid paging the processor.
- The Dallas DS18B20 Digital one-wire sensors that were used as noted above have a specified absolute accuracy of .5C with a .2C accuracy between 20 -30C temperature range. They also have resolution down to .0625C which is very good, and because they are digital they are not affected by the wiring or length of wire like thermocouples are.
- Pump – Swiftech MCP-35X with reservoir. I think this pump represents the pumping power available to many users and gives a fair amount of strong pumping power and the PWM capability makes for easy variable pumping power levels
- Radiator – The Feser Company (TFC) 480 ER radiator with Yate loon D12SL12 slow speed fans at 12V. No longer in production, but a good strong quad radiator provide roughly a 3C water/air delta when under load with the fans I’m using. The small delta means warm up time is kept to a minimum. The system will normally stabilize in under 10 minutes so there is little waste in warm up and air water variability is kept to a minimum. Users with 240 rads with similar fans should expect results to be roughly 3 degrees higher than what I have recorded.
- TIM Material – I used Arctic Cooling MX-2 for this test in a cross application method. It is considered a paste that requires very little cure and commonly enough that I felt it represent general use fairly well.
- Prime 95 Load – I used Prime 95, torture test, Custom, Min FTT 8K, Max FTT 8K, Run FFTs in place checked ON. This is an easy to use and constently loading program. It provided the most consistent loading I could find for quad cores. OCCT wasn’t capable of maintaining a full 100% load and so I feel Prime 95 is a more consistent loading routine and seems to work fine. It creates 8 100% load working threads and an extreme load.
- Stock IHS – I chose to leave the IHS alone this time since it would be more representative of what most people do.
Test Round #1 No Shim/Nozzle
I initially tried a round of tests without any shim or nozzle and basically got EK Supreme V1 results. It was good, but not quite equal to the latest top blocks. Upon careful examination of the TIM spread between block mounts is was very clear that I was having trouble with the block being too flat (Not enough bow). I couldn’t even get the spring pressure to be of normal pressure (40lbs) as 30 lbs performed worse than 20lbs which is also another clear indicator. Over my many block tests this past few months, I’ve been learning to look more closely at not only the numbers but also the TIM paste spread after you remove the block. The spread pattern left behind actually is the most telling thing you have to understand how the bowing features are working. Ideally you want to see the paste very thin in a nice oval over the core area with thicker paste along the perimeter. This is what I was getting with the M6 without any shims in place:
I just could not get that perfect mount. So, I gave up on the non-shimmed round and moved onto shim/nozzle testing to see if the mechanical contact could be improved.
In hindsight, I should have skipped the thermal testing and gone straight to the shims as the TIM spread visual is enough to show a change was needed.
Test Round #2 .005″ Shim, 090″ Nozzle
First I tried a couple of thicker shims and looked at the base bow visually. They all seemed to be a bit too much, but .005″ seems like a good balance looking at the base via straightedge. I also figured the .090″ width would be a good place to start. The shim made a HUGE difference in improving that mechanical contact and perhaps also due to the narrower nozzle. The mechanical contact problem was gone with nothing more than .005″ worth of extra thickness. I also noticed in this round that rotating the block 180 seemed to help which is what I did between mounts 6 and 7. You can see below how there is no longer transparency along the perimeter and how the pressure area is nicely focused over the core area. It’s a little bit off center in this mount, but the nice oval contact patch ending inside the perimeter is exactly what you want to see in determining the proper bow.
You can see here that the bridging issue I was having is all gone now and this is with full mounting pressure too.
I made another 3 mount round, this time trying the .004″ thickness/.090″ wide shim/nozzle and these were the test results:
Basically a tie for first place with the XSPC Raystorm and Koolance CPU-370, excellent!