The last week or so my pc has started to fail, it just shuts down, all goes quiet and only the power light remains on. This often happens upon booting up, it'll fail within 2 or 3 seconds of being switch on, other times it might just about get fully started then fail and other times it might be on working fine for 2 or 3 hours then fail. What is the most likely culprit, power supply, motherboard or hard drive? I'm running XP Home with SP2 and have had no problems with it, the pc is 2.5 years old and just over a year ago I had to replace the power supply. It's AMD 2200+, 1 GB ram, ti4800 gfx card and 1 hard drive.
Many thanks for any advice, please reply quickly as currently it's working(hence I can write this!) but it may not for much longer.
Yes I have checked the fans and they are all on although when it goes dead everything is off except there is still a power light on the mb and on the front of the case. Is it safe to assume the power supply unit is OK as if that failed there would be nothing on at all, no indicator light etc(?). It's strange in that sometimes only the monitor goes off (into standby mode) but "usually" everything is off except for said power indicator lights.