Testing a PSU is not an easy task as you need to apply a load to it in order to get proper results and sadly we don’t have a load tester in the labs as yet. The only way to load the PSU was to plug it into a PC and measure how much power it draws. The PC used was fitted with a 3200+ Athlon 64 processor, 1GB of RAM, three hard drives, three optical drives, a Radeon 9800Pro graphics card and a couple of fans. This represents a pretty stacked PC and should give you an idea of how much power you can expect the PaxPower to draw.
Using a plug-in mains power and energy monitor I was able to measure the power drain from the mains socket during various situations. It might not be the most scientific way of testing, but it does show how the PaxPower would cope in a real world situation.
What impressed me was the low standby load of only 4W compared to between 9 and 11W for the PSU I previously had fitted in the system. This would save quite a lot of money in terms of wasted electricity and it is something worth considering when you’re buying any electrical appliance that has a standby mode. Booting the PC up, the PaxPower peaked at 217W which was also the highest drain at any time, but this was still 10W less than my previous PSU.
Idle in Windows XP the PaxPower varied around 142-143W, whereas my old PSU was only slightly higher at 146-147W. Extracting a large file with WinRAR, which puts a reasonable load on the CPU and hard drives brought this up to 179W versus 185W. Looping 3DMark03 the PaxPower peaked at 209W but averaged around 201W, compared to a peak of 218W and an average of 207W for my old PSU. Loading up CPU burn the PaxPower measured up at 198W while the other unit reached 211W.
Using SpeedFan to check the voltage outputs the PaxPower produced 3.23V on the 3.3V rail, 5.00V on the 5V rail and 11.90V on the 12V rail. These numbers are a little on the low side, but the measurement is dependant on how precise the motherboard reads the voltage.
Overall I’m impressed by the build quality of the PaxPower and the low standby power drain will save you money on your electricity bill, unless of course you unplug your computer every time you switch it off. The PaxPower might seem expensive at £73.44 for the blue LED fan version or £70.44 for the normal fan, but you do get what you pay for when it comes to power supply units.
The Akasa PaxPower 460W is a quality PSU with a fair amount of connectivity and it is one of the first PSUs to meet the new ATX standard with support for Intel’s new motherboard specification. It is also reasonably quiet and has a few extras in the box that that may come in handy.