Testbed and Methods

We tested all the cooling solutions discussed in this article and their competitor in two modes: in an open testbed when the mainboard sits horizontally on the desk and the cooler is installed vertically, and in a closed testbed with the mainboard in vertical position.

Our testbed was identical for all coolers and featured the following configuration:

• Mainboard: DFI LANPARTY DK X48-T2RS (Intel X48), LGA 775, BIOS 08/29/2008
• Processor: Intel Core 2 Extreme QX9650 (3.0GHz, 1.25V, 2x6MB L2 cache, 4x333MHz FSB, Yorkfield, C0)
• Thermal interface: Arctic Silver 5 (for all coolers)
• Graphics card: HIS Radeon HD 4870 GDDR5 512MB / 256bit, 750 (250) / 3600MHz
• 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).
• Disk subsystem: Western Digital VelociRaptor (SATA-II, 300GB storage capacity, 10,000RPM, 16MB cache, NCQ)
• HDD silencer and cooler: Scythe Quiet Drive 3.5”
• Optical drive: Samsung SH-S183L SATA-II DVD RAM & DVD±R/RW & CD±RW
• System case: ASUS ASCOT 6AR2-B Black&Silver (ATX) with 120mm ~960RPM Scythe Slip Stream 120 fans for air intake and exhaust (the fans are installed on silicon spindles), and the same 120mm ~960RPM fan on the side panel
• Control and monitoring panel: Zalman ZM-MFC2
• Power supply: Thermaltake Toughpower 1500W W0218 (with a default 130 mm fan)
• Monitor: 24" BenQ FP241W (Wide LCD, 1920 x 1200 / 60 Hz)

All tests were performed under Windows Vista Ultimate Edition x86 SP1. SpeedFan 4.36 beta 15 was used to monitor the temperature of the CPU and mainboard chipset, reading it directly from the CPU core sensor and to monitor the rotation speed of the cooler fans:

I would like to draw your attention to the fact that unlike SpeedFan 4.34 that I used before, the new version has corrected processor core temperature monitoring (according to the utility developer, it is corrected to match the official Intel data). As a result, CPU temperature readings increased by 7-8°C. Therefore, it would be wrong to compare these results with any results from the previous reviews without necessary corrections.

The mainboard’s automatic fan speed management feature as well as CPU power-saving technologies were disabled for the time of the tests in the mainboard BIOS. The CPU thermal throttling was controlled with the RightMark CPU Clock Utility version 2.35.0:

The CPU was heated up in two modes. First we used Linpack 32-bit with very convenient LinX shell version 0.4.9 to heat it up to its maximum. We manually set the RAM capacity at 1200MB and recorded 15 runs.

Since we ran the test twice with 20-minute idle period between the runs for the system to cool down and temperatures to stabilize, the relatively short actual testing period was quite enough for the maximum processor temperature to become stable. The complete screenshot from the test run is given below:

Moreover, since Linpack 32-bit algorithm generates not quite typical workload for the CPU, which you will hardly come across in any other application, we decided to also test our systems in a very resource-hungry game – Unreal Tournament 3 - that works with all four processor cores. During the test the “Fly By” scene was run 5 times at “DM-ShangriLa” level with the help of HardwareOC UT3 Bench v1.3.0.0 benchmark. To minimize the dependence of the CPU performance on the graphics card we tested in 1280x1024 resolution but with maximum image quality settings. Even in this mode Radeon HD 4870 working at its nominal frequencies delivered average framerate of 174~177 fps.

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 took about half the time. Despite the stabilization period, the result of the second test cycle was usually 0.5-1°C higher. The maximum temperature of the hottest CPU core of the four 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).

The ambient temperature was checked next to the system case with an electronic thermometer that allows monitoring the temperature changes over the past 6 hours. During our test session room temperatures varied between 25.0°C. It is used as a starting point on the temperature 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.

The noise level of each cooler was measured after 1:00AM in a closed room about 20sq.m big using CENTER-321 electronic noise meter. The measurements were taken at 3cm, 1m and 3m distance from the noise source. During the acoustics tests all three 120-mm case fans were slowed down to ~700. In this mode the background noise from the system case measured at 1m distance didn’t exceed ~32.8 dBA, and the loudest fan was the 130-mm fan of the system power supply. When the system was completely powered off, our noise meter detected 30.8 dBA (the lowest on the charts is 30 dBA. The subjectively comfortable noise level is around 34~34.5 dBA.

We will be comparing the cooling efficiency of our today’s testing participants against that of an inexpensive but very efficient ZEROtherm ZEN FZ120 ($40) with a standard PWM fan rotating at 1290~1800 RPM:

Including the cooling efficiency references such as Thermalright SI-128 SE or Thermalright IFX-14 into a modding cooler roundup would be similar to including Radeon HD 4870 into GeForce 9600 GT testing session. Therefore, none of the Thermalright solutions will participate this time. However,w e also added the results of an aluminum Thermaltake MaxOrb cooler in order to compare its performance against the copper one. Unfortunately, I didn’t have the copper V12 at the time of tests, so I couldn’t compare the efficiency of the V1 AX against the copper model this time. So, all in all, there will be 6 coolers participating in our today’s test session.