Before we begin, it is worth mentioning that we had faced power problems in the past, initially with a Heroichi Win Power 550W PSU, which is supposed to support the Nvidia SLI.
More specifically, the Heroichi Win Power 550W couldn't run the 3D Mark05 benchmark to its end. Usually, the PC would shut-down during the 3rd test. We tried running the tests after disconnecting the chassis fans, DVDs and the second HDD, but unfortunately, the results were the same. We then used a certified SLI PSU from Akasa, the PowerPlus 650W. However, our problems were not totally fixed. The PSU was able to run the 3D Mark05 benchmark if three fans were installed, but when we decided to install the fourth fan, the PC shut-down during the 3rd test. :-(
The output power specs for the Akasa PowerPlus 650W are given in the following table:
We used the Speedfan utility in order to check the voltages on our system with the Thermaltake Power Express 250W installed. We took two measurements, one in idle and one while running the 3DMark2005 benchmark. In the latter case, we also set the rotation speed of our four fans (3x120mm, 1x80mm) to maximum for more power consumption. Our system has two XFX 7800GTX VGA cards in SLI mode, two hard disk drives and two DVD burners.
The following table lists industry wide specifications for DC Output Voltage Regulation.
- Thermaltake Power Express 250W
And YES!! we were finally able to run the 3D Mark05 benchmark with four fans and without having any power problems.