With the introduction of power hungry video setups like Crossfire and SLI, having a PSU that does what it says on the tin is more important than ever. A number of magazines and websites have conducted scientific tests of power supplies in recent months, measuring their peak loads and cut-off points, as well as their efficiency. Whilst this is quite useful data, I don’t believe it is an accurate representation of how a real PC works.
Instead, we have borrowed one of the most demanding PC configurations known to man to test our PSUs in a real-world environment – the Chillblast Fusion X4 workstation. Into this beast we have quad-opteron 275 cores, a Tyan K8WE motherboard, and 16GB of memory. After this the spec gets really interesting, as we also have dual Quadro FX 4500 (the workstation variant of the 7800 GTX 512MB) video cards and a RAID 5 array of ten (yes, TEN) 10,000 rpm drives. According to my handy PSU calculator, at peak load this machine actually requires somewhere in the region of 550W, so any of today’s competitors not delivering their advertised output are going to be in trouble.
When judging the PSUs, we measured the wibble from the recommended rail voltage whilst running a suite of intensive benchmarks, including PCMark, Prime95 IOMeter, FarCry and Half Life 2. These were done with a number of USB devices also attached to really max out the power. We left each PSU running for 12 hours to ensure its stability and recorded the values.
We have a total of six contenders available today, and all of them are probably already on your shortlist if you are looking for the best possible PSUs on the market. We have entrants from Antec, Enermax, Tagan, Seasonic, Hiper and OCZ, all of which have provided models in the 550W-600W range. On to the testing!
