I've been experiencing some system instability and have eliminated pretty much everything bar my PSU. It's a coloursit 400W unit and i'm running a prescott P4, Abit IG-80 mobo, Saphire Radeon X1650 pro, and two sticks of kingston value ram and a Maxtor 120gig sata hdd. No optical or floppy drives. no fans bar the CPU and GPU cooler. Modest power requirements I guess.
The hard drive sometimes clatters and cuts out but is always fine on a restart. I thought this was a temp problem initally but i get this error at both 30c under load with a fan and 60c under load with no fan so i'm not sure its a temp issue. I get seemingly random errors and slow performance before everything speeds up again. I'm clean of viruses/adaware and have cleaned the registry too.
Basically, Is this a power issue? I'm aware the brand of my psu is pretty poor but i really dont have the cash to blow on a new one if it's not faulty.
Could be the PSU. Could be the RAM. Have you run MemTest? Also, it could be an overheating chipset. Trying pointing a fan at it, then go through some tasks that would cause it to shutdown/restart. Also, check your event logs, that might give you a clue, and turn off automatic reboot so if you do get BSOD, you can see the error message.