Computer Shut Off

Good morning. I have a desktop I built myself in 2006. About two months ago, my desktop began to randomly shut off, then I would have to reset a few times to get it to turn back on. When it shut off, the lights on the front of the case would blink at one second intervals. ( One second on, one second off for a minute or so then turn off ) The fan on the case as well as the processor and lights would still be on. There would be no sound from the motherboard. I had figured it was a bad RAM slot, so I tested each slot and found ( or so I thought ) that Slot 3 was causing this issue. Removed the RAM from this, and it ran just fine until yesterday. A month after removing the RAM from Slot 3, my house had a power surge, and now when my desktop is shut off ( no OS running ) the fans and lights were still on. Not a big deal to me, as the desktop was still running. Yesterday afternoon, my desktop shut down again ( like it did when the bad memory slot was an issue ) and will not turn on again. The fans and lights are still on, however there are no lights blinking on the fron of the tower like before. There is also no beeps resignating from the motherboard. I am wondering if the power supply is shot, or if the problem would lie in my motherboard, or elsewhere I've not looked yet. Any help you could provide would be greatly appreciated. Thanks! Alex

That does not sound good, and it wont be easy to identify the issue, because there is a high possibility it could be more than 1 component at fault from your situation, power surges are bad, they kill entire systems in the worst case, I take it you have no kind of surge protection ? I strongly suggest you get some ASAP to minimise any future recurrence of such a situation, a UPS is the ideal, but they aren't cheap, but a surge protector is far better than nothing.

To begin you will need a PSU tester or a meter and the ability\knowledge on how to use it, without this you wont be able to prove the PSU one way or the other, you can buy such testers quite cheaply these days, but hopefully you know someone who has one, but given the circumstances you certainly need this to check the PSU, Here is an example(s) of such testers.
Now the ram slot, it is highly possible you had taken a surge previously, but not so you'd notice, ram is very sensitive and can be easily upset\damaged, you can test the sticks of ram by running MemTest, it will show if a stick has gone bad, if the sticks are proved to be good, then the board itself is probably at fault, unfortunately there is no clear direct test to check the board, many times it is a leap of faith by proving everything else to be OK, thus leaving the board as the unknown.

So really the 1st step is to check the PSU, unless you can power on you can't do anything else, not unless you have a comparable system to swap parts about for testing purposes, there is 1 other possible to do if possible, if you have access to another PSU then simply swap yours for the other one for testing purposes, if everything fires up then it's pretty certain the PSU has gone bad, but either way, once the PSU is sorted it doesn't mean there are not further issues that will still require attention, but see what you can do about the power and we can go from there.

Should you opt to buy a new PSU do NOT skimp on it, by the biggest and best you can afford, not just the minimum to get the system started, because that is a false economy that will cost you more in the long run if things go bad, because worst case you could be back here again with another fried system, because when a PSU goes bad it can take the entire system with it, but the best PSU's out are by PCP&C IMHO, but there are other good makes for less, but these are the Rolls Royce in PSU's, hope this gets you started anyway.