Need help building a PC

[ODogg]

Ok guys, I need any insight any of you can provide. About 2 1/2 years ago I used to have a pretty good computer but had some issues with it related to MS Windows so I just went and bought a new one. There was really nothing wrong with the old PC save it was old and the case was somewhat beat up.

So I told my niece i'd transfer to a new case, reformat the drive and give the PC to her. Well I finally got around to it in late summer but when I was done transferring to the new case and had everything hooked up, hit the on switch and held my breath........nothing at all happened. No power supply turned on, no fans went on, nada. Absolutely nothing at all happened.

So thinking it was the power supply I finally, a few months later (re this past week), went online and bought a new, albeit cheap $12 power supply (400w). Well first of all I plugged this into the wall at work and nothing happened when I turned it on. I thought, well maybe if it's not hooked to a PC motherboard is why it won't come on?

I just now hooked everything up to the new PC and here is what happens. Well not much at all happens, the power supply fan doesn't come on. All that happens is the CPU fan faintly (VERY faintly) moves, and a tiny, green light on the motherboard comes on.

So am I the unluckiest person in the world to have two bad power supplies or what? Should a power supply come on if it's not connected to a PC? I would think it should. I don't want to sink any more money into this as the whole reason for doing this was to salvage an old PC.

Also - for all the people who when I ask about buying a new PC who say "just build one, it's not that hard".....this is the crap that is annoying to me as to why I don't choose to build my own!!

[Chaos81]

Re: Need help building a PC

Why not try the one in your new computer? It might be a pain, but it wouldn't take long, and would be an easy way to find out where the problem is. What parts are on the computer? Motherboard and so on? I only ask because certain motherboards can only use certain power supplies. Also, where did you buy the new PS?


Much like before when you posted, if your power supply fan isn't turning on, that's normally an issue with the power supply. It sucks that you got a bad one, but it happens.

I had the same issue with modems not long ago. The one I had broke. The new one I got from TWC was broken as well.

[mudtiger]

Re: Need help building a PC

Power supplies will not work without a connection to the motherboard, you need some load. You could do the paper clip trick to short it and test it without a mobo connection, but I wouldn't suggest you do that.

Odd though that the mobo light goes on when connected. Is there a light on the mobo on all the time? Or does it only come on briefly when you push the switch?

The 5v connection on my last psu went haywire and the psu actually worked, but it didn't get enough power to send an on signal when you pushed the button, so some fans would start briefly but the computer wouldn't actually do anything.

Just to make sure, you do have the switch set to 110 and not 220?

Sounds like your 12$ psu is a piece of crap. 40-50 bucks for a 400W psu is probably as cheap as you should go. I build my own pc's and the psu is the last part I would try to go cheap on.

[ODogg]

Re: Need help building a PC

Power supplies will not work without a connection to the motherboard, you need some load. You could do the paper clip trick to short it and test it without a mobo connection, but I wouldn't suggest you do that.

Odd though that the mobo light goes on when connected. Is there a light on the mobo on all the time? Or does it only come on briefly when you push the switch?

The 5v connection on my last psu went haywire and the psu actually worked, but it didn't get enough power to send an on signal when you pushed the button, so some fans would start briefly but the computer wouldn't actually do anything.

Just to make sure, you do have the switch set to 110 and not 220?

Sounds like your 12$ psu is a piece of crap. 40-50 bucks for a 400W psu is probably as cheap as you should go. I build my own pc's and the psu is the last part I would try to go cheap on.

I do have it set to 115v which is what the manual says to set it at for American electrical. The green, small light on the motherboard comes on and stays on whenever the power supply is turned on. When it's turned off, after about 5 seconds it fades out and stays out.

You are right that the PSU is cheap and maybe a piece of crap. However the computer in general is old and not worth spending much money on is why I skimped so heavily on it. It seems like a decent power supply though honestly from looking at it (for what I intend it for).

Let me ask you guys this, would something I have hooked up wrong on the motherboard, such as say the power LED, the power on/off button, that sort of thing, prohibit the computer from posting and the power supply from powering up? Perhaps I should disconnect everything from the motherboard and just try it then.

Or as said above, I could connect the power supply up to my newer (and dead too I might add) Falcon to see if it would at least POST.

P.S. Thanks for letting me know about the "it won't turn on if it's not connected to the MOBO" info, that is what I was wondering.

[mudtiger]

Re: Need help building a PC

Yes, if you hooked something up wrong like the on/off button it could stop it from booting. You also want to check the ram and cards plugged in to make sure they are fully seated. Check all the connections.

The green light being lit means the psu at least isn't a door stop, the mobo is at least getting some power which adds to the mystery.

I'd check the connections first and if that still doesn't work, then hook it up to the other computer.

[e0820]

Re: Need help building a PC

I would make sure the CPU fan is on securely and plugged into the motherboard (or power supply) and reseat any cards like the video card or memory. If still not working I would remove the video card completley and see if it turns on.