CPU: Pentium 4 2.4GHz C-stepping
RAM: 1GB Ultra
VGA: Sapphire Radeon 9700
HDD: 1 Seagate 60GB, 1 Western Digital 120GB
DVD: 1 Pioneer DVD, 1 Shuttle DVD?RW
Mods: 4 Sunbeam cold cathode lights, 2 Sunbeam LED laser lights

With all that hardware, we let the supplies settle in at idle before stressing them out. For our stress test, we set our rig to play an MPG movie, copy a 500MB file from one hard drive to the other, copy 650MB of CD-written files from the DVD drive to the hard drive and run the Sandra CPU benchmark, all simultaneously. We also switched on all the cathodes and sent our lazer lights a-buzzin'. Quite a workout, and far more difficult for our test subjects to cope with than they would have to in any every-day scenario. We measured the results by watching Motherboard Monitor with a hawk-eye...

The results are below.

As you can see from the under-load figures, there is very little variation in voltage, with most of these supplies still managing to stay above the specification voltages. This seems to be achieved by starting off at higher voltages that required - indeed, the PSUs appear to over-volt the 12V line by half a volt. Whilst this won't be enough to kill any of your devices, it's plenty to provide for a large drop in voltage whilst still powering them, meaning that the units will cope well under load.

None of the units had problems coping with our stress-test, suggesting that they're all well built and packing plenty of punch. The decision as to which to buy, then, comes down to the price and the features that you are after.

In our opinion, the Hiper is the best-looking supply out of the bunch and would befit all those who are after a top-notch unit that will be on show plenty. It also sports a 3-year warranty, which is a big plus point, and is the cheapest on show. It's hard to beat a 480W supply from a good name for around ?5. The ModStream is compelling because of the flexibility that the connection system provides. OCZ also bundle a 3-year warranty with the unit, and their legendary service means this should be a major selling point. The Enermax has the highest feel of quality about it, and its 600W will be lusted after by those who have plenty of peripherals to power. It is, however the most expensive - but we think you get what you pay for, and in terms of raw power and solid operation, it's our choice.

Check out further details on the units here: