New CPU Cooling Test Configuration

All Cooling tests were run on the new cooling test bed, which is a Rosewill R604-P-SL case sold without a power supply. The Rosewill is a brand typical of a moderately priced mid-tower case our readers might own. It was chosen because it is a Newegg top seller and includes a variable front intake louver and a quiet 120mm exhaust fan at the rear of the case. The case is also screwless with components held in place by plastic holders instead of metal to metal connections. This appears to reduce case vibration and noise.

The new power supply is a Corsair HX620W, which has earned our respect as an exceptionally quiet PSU with a variable speed exhaust fan and a down-facing fan mounted just above the CPU space in the case. To eliminate the video card as a source of noise we have moved to a fanless video card. Since the move will be made to Vista and DX10 in the near future, the testbed runs an MSI NX8600GTS which supports DX10 and cools with heatsinks and heatpipes. The reduced noise power supply and fanless video card have the potential to dramatically lower system noise in the test bed.

The new motherboard is the Asus P5K Deluxe. This P35 chipset motherboard has exhibited outstanding overclocking capabilities in our testing, and it can also mount the newest 1333 FSB Intel Core processors and can handle our existing high-speed DDR2 memory. The P5K3 uses heatsinks and heatpipes to cool board components so all motherboard cooling is passive. There are no active cooling fans.

Other components in the cooling test bed are generally the same as those used in our previous motherboard and memory test bed. The goal was to remove fans that might produce noise wherever possible, improve internal airflow, reduce the power supply noise floor, and eliminate the video card as a noise source.

The 120mm exhaust fan mounted to the rear of the case is below the system noise floor. We run that fan during performance and overclocking tests. However, system noise can be cumulative, so the exhaust fan is turned off during noise testing. The current fan will be replaced by the lowest noise 120mm fan when our 120mm fan roundup is completed.

Cooling Performance Test Configuration
Processor Intel Core 2 Duo X6800
(Dual-core 2.93GHz, 4MB Unified Cache)
RAM 2x1GB Corsair Dominator PC2-8888 (DDR2-1111)
Hard Drive(s) Hitachi 250GB SATA2 enabled (16MB Buffer)
Video Card MSI NX8600GTS (fanless) - All Standard Tests
Intel TAT Version 2.05.2006.0427
CoreTemp Version 0.95
Video Drivers NVIDIA 163.71
CPU Cooling OCZ Vendetta
Scythe Kama Cross
Swiftech H2O-120 Compact
Corsair Nautilus 500
Thermalright Ultima-90
Thermalright Ultra-120 eXtreme
Intel Retail HSF for X6800
Power Supply Corsair HX620W
Motherboards Asus P5K Deluxe (Intel P35)
Operating System Windows XP Professional SP2
BIOS Asus AMI 0501 (06/26/2007)

All cooling tests are run with the components mounted in a standard mid-tower case. The idle and stress temperature tests are run with the case closed and standing as it would in most home setups. We do not use auxiliary fans in the test cooling case, except for the aforementioned case fan. Room temperature is measured before beginning the cooler tests and is maintained in the 20 to 22C (68 to 72F) range for all testing.

For consistency of test results we tested with our standard premium silver-colored thermal compound. In our experience the thermal compound used makes little to no difference in cooling test results. This is particularly true now that processors ship with a large manufacturer-installed heatspreader. Our current test procedure uses this standard high-quality silver-colored thermal paste for all cooler reviews.

We first tested the stock Intel air cooler at standard X6800 speed and measured the CPU temperature at idle. The CPU was then stressed by running continuous loops of the Far Cry River demo. The same tests were repeated at the highest stable overclock we could achieve with the stock cooler. Stable in this case meant the ability to handle our Far Cry looping for at least 30 minutes.

The same benchmarks are then run on the coolers under test at stock, highest stock cooler OC speed (3.73GHz) and the highest OC that could be achieved in the same setup with the cooler being tested. This allows measurement of the cooling efficiency of the test unit compared to stock and the improvement in overclocking capabilities, if any, from using the test cooler.

The cooling test results of both the OCZ Vendetta and the Scythe Kama Cross are compared to a representative sample of air and water cooling results that were measured with CoreTemp. TAT provides a similar core measurement, but test results with CoreTemp were more consistent over a wide range of test conditions than the results reported by TAT. Coolers retested with CoreTemp under idle and load conditions were the Intel retail cooler, the Thermalright Ultra-120 eXtreme, and the Thermalright Ultima-90. The Ultra-120 eXtreme is the best performing air cooler tested at AnandTech, where the Ultima-90 is a smaller cooler that matches performance of other top coolers when fitted with a 120mm fan. Two recently tested entry-level water cooling systems are also included, along with results from tests of the OCZ Vendetta and Scythe Kama Cross.

In benchmarks where the new test bed makes no apparent difference, like maximum overclock, results are reported for all coolers tested this year.

Noise Levels

In addition to cooling efficiency and overclocking abilities, users shopping for CPU cooling solutions may also be interested in the noise levels of the cooling devices they are considering. Noise levels are measured with the case on its side and are measured using a C.E.M. DT-8850 Sound Level meter.

This meter allows accurate sound level measurements from 35bdB to 130dB with a resolution of 0.1dB and an accuracy of 1.5dB. This is sufficient for our needs in these tests, as measurement starts at the level of a relatively quiet room. Our own test room, with all computers and fans turned off, has a room noise level that has been reduced slightly to 35.0dB compared to the previous 36.4 dBA. With the new testbed, the system noise at idle is 36.5 dBA at 24" and 37.8 dBA at 6". This is better than our previous system noise floor of 38.3 db at 24". The noise reduction at the 6" distance is dramatically lower than the previous test bed floor of 47 dBA.

Procedures for measuring cooling system noise are described on page six which reports measured noise results comparing the stock Intel cooler and retested CPU coolers to the OCZ Vendetta and Scythe Kama Cross.

OCZ Vendetta Cooling at Stock Speed


View All Comments

  • rbuffetta - Tuesday, October 02, 2007 - link

    Spend the extra $20-30 and get the Thermalright Ultra 120 Extreme. Of all the places to cut corners and save money this is really where it counts to protect your cpu and allow for decent overclocks. Reply
  • EtherealDragon - Tuesday, October 02, 2007 - link

    As always, it was a nice read, but why oh why would you plot the 2 graphs on page 7 in that manner? Seems funny to me to have the points on the graphs "drop" as the temperature raises... I guess thats just my .02 Reply
  • Wesley Fink - Tuesday, October 02, 2007 - link

    It's very easy to change the chart with temp going up if enough readers prefer it. We changed the graph scale after receiving several complaints that the top performance was the lowest chart position on the old charts and difficult to comprehend. If more readers prefer the original chart layout we will be happy to change back. Please let us know. Reply
  • strikeback03 - Tuesday, October 02, 2007 - link

    I prefer the old orientation, as it makes sense to me that when you are looking for the cooler with the lowest temperature, you look at the lowest point on the graph. Reply
  • Sentrosi2121 - Tuesday, October 02, 2007 - link

    Pretty acceptable for the OCZ cooler. I wonder how it would perform inside an enclosure like the X-Qpack. I'm trying to build a nice gaming rig with the X-Qpack and would like to see if it would fit inside. Reply
  • Basilisk - Tuesday, October 02, 2007 - link


    I wonder how it would perform inside an enclosure like the X-Qpack.

    Depends on your skill with a hammer and chisel: The X-Qpack (and X-Qpack2 and Ultra Micro Fly) only have about 75mm of headroom above the CPU -- challenging for a 92mm fam mounted perhaps 40mm above the CPU! Go with a Zalman horizontal flower (7000, 7700, 8700), a few other units or just the stock fan in those cases.

    PS: The X-Qpack2 has improved airflow and clearance (length) over the X-Qpack.
  • Anonymous Freak - Tuesday, October 02, 2007 - link

    StorageReview just did a review of the">Western Digital "Green Power" 1 TB hard drive. While it's not the best performing drive in the world, it's no slouch, and it has the side effect of being the quietest drive they've ever tested. (Plus it runs cool enough that you could probably slap it in a Reply
  • EtherealDragon - Tuesday, October 02, 2007 - link

    As always, it was a nice read, but why oh why would you plot the 2 graphs on page 7 in that manner? Seems funny to me to have the points on the graphs "drop" as the temperature raises... I guess thats just my .02 Reply
  • Phil Harris - Monday, October 01, 2007 - link

    It seems utterly ridiculous to me that these coolers are tested on dual setups.
    If someone looking to build a quad is trying to find useful information, this review is completely pointless.

    A test on a quad however will still provide useful info to someone building a dual core.

    The defence that games don't use quads yet is also totally specious, if thats the reason, why bother testing anything other than dual core machines?

    Lets all ignore quad core computing until we can play games on them... is that the idea?

    This is the second poor quality review in the cases and cooling section within a few weeks, if Anandtech wants to be taken seriously, a serious re-think is required.
  • Acanthus - Monday, October 01, 2007 - link

    Many enthusiasts that are spending money on components for overclocking have opted for cheap quad cores.

    Sorry to sound frustrated, but this is getting rediculous when we are in the world of $270 quad cores.

Log in

Don't have an account? Sign up now