Testbed and Methods

AeroCool cooling solutions and their two competitors were tested on an open testbed as well as in a closed system case with the following configuration:

• Mainboard: ASUSTek P5K Deluxe/WiFi-AP (Intel P35), LGA 775, BIOS 0705
• Processor: Intel Core 2 Duo E6750 2667MHz, 1.35V, L2 4096KB, FSB: 333MHz x 4, (Conroe, G0)
• Thermal interface: Arctic Silver 5
• Graphics card: HIS Radeon HD 3870 graphics card (GDDR4 512MB/256bit, @864/2520MHz)
• Graphics card cooler: Arctic Cooling Accelero S1 (in passive mode)
• Memory:
  • 2 x 1024MB DDR2 Corsair Dominator TWIN2X2048-9136C5D (1142MHz / 5-5-5-18 / 2.1V)
  • 2 x 1024MB DDR2 CSXO-XAC-1200-2GB-KIT DIABLO (1200MHz / 5-5-5-16 / 2.4V)
• Memory cooler: CoolIt RAMfan (70x15mm, ~2500 RPM)
• Disk subsystem: Samsung HD501LJ HDD (SATA-II, 500GB storage capacity, 7200rpm, 16MB cache, NCQ)
• Optical drive: Samsung SH-S183L RAM & DVD±R/RW & CD±RW burner (SATA-II)
• System case: ASUS ASCOT 6AR2-B Black&Silver (ATX) with 120mm ~900RPM Scythe Minebea fans for air intake and exhaust, and a 120mm ~900RPM GlacialTech SilentBlade GT12025-BDLA1 fan on a side panel
• Power supply: Enermax Galaxy EGA1000EWL 1000W (a 135mm 850RPM fan for intake).

The dual-core Intel Core 2 Duo E6750 processor with G0 core stepping overclocked to a pretty decent speed of 3600MHz when working with the weakest cooler of our today’s testing participants in its quiet mode. The processor Vcore was increased to 1.55V:

Monitoring utilities reported much lower voltage setting than what we set in the mainboard BIOS – it was around ~1.5375V. It dropped down to ~1.525V under heavy load (click to enlarge):

All tests were performed in Windows XP Professional Edition Service Pack 2. SpeedFan 4.34 Beta 38 was used to monitor the temperature of the CPU, reading it directly from the CPU core sensor:

Its readings matched those of the Core Temp 0.96 utility. The mainboard’s automatic fan speed management system was disabled for the time of the tests in the mainboard BIOS. The CPU thermal throttling was controlled with RightMark CPU Clock Utility version 2.30:

The CPU was heated up with OCCT (OverClock Checking Tool) version 1.1.1b in a 23-minute test with maximum CPU utilization, during which the system remained idle in the first and last 4 minutes.

I performed at least two cycles of tests and waited for approximately 20 minutes for the temperature inside the system case to stabilize during each test cycle. The stabilization period in an open testbed with the mainboard in horizontal and coolers in a vertical position took about half the time. The maximum temperature of the hottest CPU core of the two in the two test cycles was considered the final result (if the difference was no bigger than 1°C – otherwise the test was performed at least once again). Despite the stabilization period, the result of the second test cycle was usually 0.5-1°C higher.

The noise level of each cooler was measured according to our traditional method described in the previous articles with the help of an electronic noise meter – CENTER-321. We have reduced the subjectively comfortable noise level from the previously used 36dBA to 34.5dBA and is marked with a dotted line in the diagram. To illustrate what this noise level is like we can say that it is the noise generated by a high-quality single 120x25mm fan with ~1100~1150RPM rotation speed. The ambient noise from the system case without the CPU cooler didn’t exceed 33.4dBA when measured at 1m distance.

The ambient temperature was checked with an electronic thermometer that allows monitoring the temperature changes over the past 6 hours. During our test session room temperatures stabilized at around 25°C. It is used as a staring point on the diagrams. Note that the fan rotation speeds as shown in the diagrams are the average readings reported by SpeedFan, and not the official claimed fan specifications.

First of all we will compare AeroCool cooling solutions against a standard boxed cooler that comes bundled with Intel CPUs. This will allow us to estimate how much more efficient and quieter the new AeroCool solutions are compared with what Intel has to offer these days. At the same time we have also tested a popular and pretty efficient Cooler Master Hyper TX 2 bundled with a standard fan rotating at ~1880RPM. The recommended retail price for this cooler is around $22 and it is currently one of the leaders in the mainstream cooling solutions segment.