As the threat title goes, my PSU just died today with a glorious pop and spark of electricity. Before I go further, I'll detail the specs and some history:

ASUS A8N-SLI Motherboard
PSU (while it was still alive): PP500 500W
1 GB RAM
nVidia GeForce 7900 GTX (Later upgraded to 8800 GT)
AMD 64 X2 2.4 Ghz

I had this computer built around three years ago, and it's served me well. I tended to leave the computer on for most of the day, turning it off in the evening before I went to bed. Roughly two months ago, my graphics card started showing sporadic artifacts in some games, but it never really got worse until just a couple of weeks ago. I invested in an 8800 upgrade and popped it in, worked wonderfully. Now, just five days ago, weird things started happening. I remember coming back to the computer after dinner, and for some reason or another the computer failed to detect the sound card (A C-Media card). The hardware wizard didn't detect it at all, and after a reboot it still failed to detect it. It wasn't until the third reboot that the sound card started working again. However, things still got worse: during bootup the USB ports will fail to turn on, and my network connection would disconnect though the ethernet port lights were still on, on top of the sound card issues. Now, today I tried booting the computer up again. Things were going fine until a blue screen popped up with an error message stating that a piece of hardware didn't boot up properly (I should have written down the exact message, but that was the basic jist of it). I turned the machine off and started it up again, but this time only the fans, LEDs, and drives would turn on, and my monitor remained black. The second time I tried rebooting it, the PSU popped.
Now, when these problems started, I had an inkling that the PSU may have been the culprit. With it having expired, I still think the power supply was the cause of the problems but, before I invest in a new one, I'd like to figure out if there's any collateral damage I should know about. A new PSU and mobo wouldn't be too much of an issue for me, but I'd like to get an idea first with the hopes of saving some money. Sorry for the lengthy post, but I thank anyone in advance for their input.

You could always just replace the PSU and run the system bare minimum (cpu, ram, video) and see if it all works. Then add the other add-on cards, drives, etc and see if it all works. It sounds like you'll have to replace the PSU anyway, so this would probably be a good way to do it. Either that or you could try your components in another system and see if they work.

Well if you want your computer to run again i would suggest buying a new PSU and with the upgrade to an 8800 i would suggest a 750W especially with that AMD CPU. but the above post is correct. just start with the bare minimum and add stuff from there one piece at a time.