I've had this computer for a few years and in my mind - it has always underperformed. On average, I've been looking at 40fps on medium settings in world of warcraft.

Sometimes when I switch it on, the computer boots up, hdd's spin up and fans and lights turn on but the screen remains black and on standby as if nothings plugged in. To check the screen wasnt a problem I switched monitors with a friend, my screen worked fine for him but I still had the same problem with his screen when it was plugged into my pc. Might only happen about 5 times a week.

It's not like I'm running out of ram or using too much power, as task manager shows 3gb used. The gpu max's out though when I'm playing a game, using 100% of the gpu and memory, which I assume might be normal when playing a game?

I thought it might have been the power supply so switched out for a new one about a year ago. I was using a 750w tagan power supply. Once I switched the problem stayed the same.

The specs are:

i7 920 @ 4ghz

6gb corsair dominator gt RAM - triple channel

ati 5850 gfx

windows 7 64 bit.

700w corsair power supply.

No temperature on the system exceeds 60 degrees celcius even under load (water cooling).

I also did a clean install of windows at the same time the new power supply went in, the problem persisted.