Testbed and Methods

All tests were performed inside a closed system case. We used a testbed with the following configuration:

• Mainboards:
  • DFI LANPARTY DK X48-T2RS (Intel X48), LGA 775, BIOS from 10/03/2008;
  • ASUS P6T Deluxe (Intel X58 Express), LGA 1366, BIOS 1606;
• Processors:
  • Intel Core 2 Extreme QX9650, 3.0 GHz, 1.15 V, L2 2 x 6 MB, FSB 333 MHz x 4, (Yorkfield, C0);
  • Intel Core i7-920, 2.67 GHz, 1.25V, 4 x 256 KB L2, 8MB L3 (Bloomfield, C0);
• Thermal interface: Arctic Silver 5;
• Memory:
  • DDR2 2 x 1 GB Corsair Dominator TWIN2X2048-9136C5D (Spec: 1142 MHz / 5-5-5-18 / 2.1 V);
  • DDR2 2 x 1 GB CSX DIABLO CSXO-XAC-1200-2GB-KIT (Spec: 1200 MHz / 5-5-5-16 / 2.4 V);
  • DDR3 3 x 1 GB Corsair DOMINATOR TWIN3X2048-1800C7DFIN (Spec: 1800 MHz / 7-7-7-20 / 2.0 V);
• Graphics card: ZOTAC GeForce GTX 260 AMP2! Edition 896 MB, 648/1404/2108 MHz (1030 RPM);
• System HDD: Western Digital VelociRaptor (SATA-II, 300 GB storage capacity, 10,000 RPM, 16 MB cache, NCQ) inside Scythe Quiet Drive 3.5” HDD silencer and cooler chassis;
• Backup HDD: Western Digital Caviar Green WD10EADS (SATA-II, 1000 GB, 5400 RPM, 32 MB, NCQ);
• Optical drive: Samsung SH-S183L;
• System case: Antec Twelve Hundred (front panel: two Noiseblocker NB-Multiframe S-Series MF12-S1 fans at 820 RPM and Scythe Gentle Typhoon fan at 840 RPM; back panel: one Scythe Slip Stream 120 fan at 840 RPM; top panel: standard 200 mm fan at 400 RPM);
• Control and monitoring panel: Zalman ZM-MFC2;
• Power supply: Zalman ZM1000-HP 1000 W (with a default 140 mm fan and a power consumption monitoring panel).

All tests were performed under Windows Vista Ultimate Edition x86 SP1. We used the following software during our test session:

• Real Temp 3.30 RC10 – to monitor the processor core temperature;
• Linpack 32-bit with LinX shell version 0.6.0.2 – to create maximum CPU load (two test cycles, 15 Linpack runs in each cycle with 1624 MB RAM capacity involved);
• RivaTuner 2.24 – to visually control temperature changes (with RTCore plugin).
• CPU-Z 1.51 – to monitor processor core voltage and frequency.

So, the complete screenshot during the test session looks as follows:

The workload was created with two consecutive Linpack runs with the settings described above. The stabilization period for the CPU temperature between the two test cycles was about 10 minutes. We took the maximum temperature of the hottest processor core of the four for the results charts. The ambient temperature was checked next to the system case with an electronic thermometer with 0.1 °C precision that allows monitoring the temperature changes over the past 6 hours. During our test session room temperature was unusually high and stayed at 25.5-26 °C.

Today we are going to compare the cooling efficiency of the testing participants not in quite common manner. The thing is that we tested Alphacool kit right after Thermaltake PW880i, which we have already referred to multiple times today. So, I decided to take advantage of this situation and performed the following tests. I took the performance of Thermaltake PW880i with Thermaltake PWB100 as a reference point for the analysis. Then I replaced the original Thermaltake dual-section radiator with triple-section Alphacool NexXxoS Xtreme III radiator with three ebm-pabst fans. I ran all tests for this configuration. After that I replaced the original Thermaltake pump and expansion tank with Alphacool Laing DDC and again ran multiple tests. In the end I replaced Thermaltake PWB100 water block on the Intel Core i7 processor with Alphacool NexXxoS XP and ran all efficiency tests all over.

So, in the end there was only coolant from Thermaltake PW880i and the retention plates for the radiator left in the system. Even the hoses were replaced with Alphacool’s original ones (they have the same cross-section, but are more robust. The cherry on top of this step-by-step modification of Thermaltake PW880i was the use of three Noiseblocker fans (1830 RPM) on the radiator instead of the ones by ebm-pabst. By the way, the latter fans were tested in three different speed modes: at very quiet 850 RPM, moderate 1170 RPM and maximum speed of 1550 RPM. I believe you understand why it was especially interesting to check out the results of such test session: this way we can determine the contribution from each liquid-cooling system component into the resulting cooling efficiency.

Besides Thermaltake PW880i liquid-cooling system, we also added the results ofThermalright IFX-14 with two Noiseblocker NB-Multiframe MF12-S3HS fans working in quiet mode at 1110 RPM and at maximum rotation speed of 1830 RPM, according to monitoring data:

In addition, we tested our system on an Intel Core 2 Extreme QX9650 LGA775 processor in order to compare the efficiency of Alphacool NexXxoS XP and Alphacool NexXxoS X2 Hiflow Bold water blocks, since the latter cannot be installed onto LGA1366.