Good evening all...

The kit:

ECS K7S5A Mobo
512MB DDR (though only showing 256MB)
nVidia GeForce2 Ti 64MB GFX adaptor
AMD Athlon XP+ 1500 (running 1300Mhz)
Windows XP Home with no service packs

The problem!

A few days ago, I was playing World of Warcraft (shh) and suddenly my monitor went black, and told me I had no signal. I thought it had simply restarted, but upon a press of the reset button, nothing appeared on the monitor, POST didn't give its normal single beep, and and odd 'grinding' noise lasting about half a second was evident.

I thought the gfx card had simply overheated, so I checked to see if the fan was spinning, which indeed it was. Left it to cool down, booted up again fine. So I restarted again, same problem with the no booting, but this time the fan WAS spinning.

Managed to boot into safe mode after a while, tried a virus scan, but it restarted after I could complete the scan.

Most of the time, it won't boot to POST, there is no signal to the monitor, and the hard disk activity light stays on. System and gfx card fans spinning up like usual, the same for the hard disks.

Other times, it will boot into XP, but hang (no blue screen of death, just freezes and will not respond to anything but me kicking the reset button) at seemingly random times. Sometimes it will be just after XP has loaded, others it will be fine for a few hours, then hang.

I have noticed, also, that my system memory is being displayed as 256MB, whereas I am sure I have 2 sticks in there, totalling 512MB. Could this be related?

Apologies for the long post, but thought it best to give as much information as possible.