We put our system under what can be considered a heavy user load, using extreme CPU and graphics 3D use with 3D Mark 06 v1.0.2. Our test PC setup was as follows:
All PSU ratings were monitored with Everest Ultimate Edition v3.0. The following table lists the industry wide specifications for DC Output Voltage Regulation.
After running 3D Mark 06, the monitored outputs showed the deviation experienced by each rail during the stress tests:
The results are very good. All ratings are well within limits. Even at full load, the voltage only deviates by 0.01~0.08V. Adding a second Nvidia 8800GTX VGA card in your system will put additional load on the PSU, but this PSU can handle it without any problems.