Computer won't boot, nothing happens, help?

If your PSU still works, and nothing else seems to work, I would say the Mobo is bad. If you have another machine, try that. No fans turn on even, the case fans?

Are the case fans plugged into fan headers on the Mobo?

Hello OldHenry,

If you want to tackle this yourself this is how I would probably proceed.

If I am understanding you correctly, it sounds like your power supply is shot or nearly so. I seriously wouldn't trust it unless someone with a working psu tester can verify otherwise and that may cost you nearly enough to simply buy a new power supply. I wouldn't recommend working on a PSU yourself due to potentially dangerous voltages present. A friend with a known good psu would be very helpful if you know such a person just to test your mobo.

Your motherboard may also be shot at this point there is no way to tell. You could buy either a replacement psu or a whole shiny new case with psu which can sometimes be had rather inexpensively if your power supply needs are not that great, i.e. you don't have a huge graphics card or six hard drives or something of that nature. Then either swap out the psu or install the old mobo in the new case with psu and fire up. If she works you're golden and if not you probably have a bad mobo, unless of course you scored another bad power supply.

If you need a motherboard, you have other issues to face. If your PC is a OEM than the Operating System is probably BIOS locked somehow to the machine, probably by virtue of a motherboard "tatoo" Buying a motherboard from an OEM is usually an expensive proposition. I would rather buy an inexpensive mobo from newegg, but then you also need a new Operating System since the old one won't install on the new mobo. You could buy an OEM version of windows with the new motherboard since this would be tantamount to a "new build." If you are going to go this route and money isn't too tight this might be an excellent time to upgrade since you are taking it all apart anyhow. Brand new mobo cpu combos are on sale daily at newegg or tigerdirect. Athlon ii x2 can be had for about $60. Next generation (sandy bridge) core i3 cpu's can be had for around $140 or so. Decent mobos for either one can be had starting at around $50 going up to $200 or more depending on what features you want.

I'd try to make sure your mobo has at least one pci express x 16 and at least one pci express x1 slot available for graphics cards and future upgrades. You'd also have to make sure that whatever cards you currently have in your machine would have a pci or pci express slot in the new mobo.

The other option that is probably ananthema to many on these boards is to simply go into best buy and buy a new system. If your needs are modest you could probably get a good internet browsing machine for $300-$400 or so and you would probably also get some warranty and keyboard and mouse.

I think he said his power supply was fine. Maybe I misunderstood.

Taking a second look maybe you are right. Although I'm confused by his mentioning of shorting out wires, maybe on the 24 pin mobo connector???

I still would want to have the psu professionally checked since you don't want to fry a new mobo with a bad psu. If memory serves there are many voltages coming off a properly functioning psu. +12v +5 +3 -5 and so on. I'm just leery of old quesitonable psu's and new mobos.

Ahhhh, I see. That would be smart.

Correct, it's the 24 pin motherboard connector from the power supply and the green/black wires (#16 and 17?) that I used a jumper on as per another post about testing power supplies. Thanks for the answers