I my quest to find out what on earth is causing random lockups, I'm starting to think it was the power supply. The reason is that the problems started soon after I put my graphics card (old Radeon X800) and the demand for power went up. Recently I've kept one monitor disconnected (was a dual monitor setup) and it hasn't locked up at all.
Before you ask about the card, the lockups don't just occur when doing graphics heavy stuff like gaming, its during normal but heavy operation. I could be viewing flash, encoding video's, fragmenting, running a virus scan, remote desktop with semi-heavy application running, or other things that don't use the card.
Unfortunately I can't tell the exact wattage of my PSU. It seems this case (old Emachines W2060) used several different power supplies and didn't list this information on the PSU itself. There's 250w (although its a stretch), 300w, and 480w PSU's available, but I'm not sure which one it is.
So my question: Could an underpowered power supply cause lockups? This would mainly be under heavy load but could also be randomly. This would happen after anywhere from an hour to 6 hours of use.
Best Answer
I think you are almost ccertainly right that the PSU is the problem Removing the case side will show you the current PSU and you can see what you have to work with. How many devices do you have - HDDs, Burners, etc? If you aren't sure try using a system profiler e.g. http://www.piriform.com/speccy Once you know what devices you have there are a number of websites that will calculate what power supply you need for your system
Type Power supply calculator into Google for the calc sites E.g. http://educations.newegg.com/tool/psucalc/index.html
If you do the tests and find that your PSU should be ok for your system config then you have 2 paths 1) is that the PSU is faulty Probably the only way to be sure is to trouble shoot by trial and error or by replacing 2) PSU isn't the problem - whole new kettle of fish
At least if you profile your system and then work out what power you need versus what you have you can work out whether that is the issue Hope that helps :)