how can i fix my computer?

July 19, 2005 1:58 AM

Computer problems...When i press power, nothing happens. It's the power supply right?

When i press power nothing happens; I know nothing is loose and i know the computer is getting power (the motherboard led is lit). I dont think there was a power surge, since my printer, router and cable modem are on the same plug and work fine. The only thing i can think of is that either the power supply is broken or the power switch is broken...Anyone know where i can get a simple On switch for my computer? And if the power supply is broken, what are the chances my other components are broken?

posted by EvilKenji to computers & internet (10 comments total)

You can simulate pressing the power switch by shorting the two pins on the motherboard that the power switch is connected to. Doing this could rule out the power switch as a problem. This is unlikely to be the issue though.

You're probably right, it could be the power supply. However, I've also seen an improperly grounded motherboard not power up at all (even with a green LED on), giving the impression that the PSU was dead. That is, no fans turned on, even the one inside the PSU. Check the connection from the PSU to the motherboard to make sure it's snug, and check the screws holding the motherboard down to make sure they're snug.

If your power supply died, it probably didn't take anything with it. At least, that's been my experience. You could hook up a PSU from another computer to see if that's the problem, or a computer shop can easily test it for you to see if it's dead or not.
posted by knave at 2:10 AM on July 19, 2005

speak in easy monkey language, how do i short the two pins on the motherboard? oh, and one more thing, this computer was working fine just yesterday.
posted by EvilKenji at 2:16 AM on July 19, 2005

I had this same problem and replaced the power supply, never having seen the inside of a PC before, and got it working again. Before unplugging everything I took pictures of what was plugged into where so I could plug it all back in the right place.

I now see 3 CD drives in Windows Explorer where I only have 2 but I'm not letting a little thing like that worry me.
posted by jontyjago at 3:21 AM on July 19, 2005

how do i short the two pins on the motherboard?

look for the wires that go from the on/off switch to the motherboard. they will end in a little rectangular plug (or plugs) that push on to two pins sticking out of the board (possibly part of a larger collection of pins, so make careful note about exactly which so that you can reconnect later). pull the plug off and carefully, using a piece of bent wire or paperclip, touch both pins at the same time.

be careful you don't touch any other pin, and be sure you have the wires from the on/off switch (rather than the speaker or reset switch, or the power or disk leds). often it says PWR on the little rectangular plug. the pins will be described in your motherboard manual, if you have one.
posted by andrew cooke at 4:42 AM on July 19, 2005

look for the wires that go from the on/off switch to the motherboard. they will end in a little rectangular plug (or plugs) that push on to two pins sticking out of the board (possibly part of a larger collection of pins, so make careful note about exactly which so that you can reconnect later). pull the plug off and carefully, using a piece of bent wire or paperclip, touch both pins at the same time.

be careful you don't touch any other pin, and be sure you have the wires from the on/off switch (rather than the speaker or reset switch, or the power or disk leds). often it says PWR on the little rectangular plug. the pins will be described in your motherboard manual, if you have one.

lol that was perhaps too much monkey language, all i needed to know was to touch the pins together :-p. Unfortunetly that didnt work.
posted by EvilKenji at 5:33 AM on July 19, 2005

you could try using a power supply tester I would no monkey around with wiring if you don't know what you are doing could cause more trouble than its worth. Testers cost about $7 Froogle Link
posted by tke248 at 5:52 AM on July 19, 2005

Take it in to a shop. It's one of two things: the power supply or the motherboard. In either case you could have a power indicator lit on the motherboard and not have the ability to really power up.

A shop should be able to determine what's up pretty quickly.
posted by plinth at 6:02 AM on July 19, 2005

It's one of two things: the power supply or the motherboard.

This is not true. 95% of the time, when a system I'm working on doesn't power up, it's because a component became unseated. Unplug all your hard drives, CD-ROM drives, remove all your RAM, etc. Put the RAM back in, so it's just your RAM and your video card -- no hard drives, or anything. Try turning it on. If it still doesn't power on, take it to a shop. If it does, then turn it off, and reconnect one component, and turn it back on. Repeat. If the motherboard led is lit, the power supply is almost certainly working.

Also, this was asked a week or so ago.
posted by Jairus at 6:37 AM on July 19, 2005

this may sound dumb, but try unplugging it. Often, motherbaords lock up in a low state of boot and simply don't power anything one. Unplug it, leave it off for about 1 minute, plug it back in and try the power button.
posted by cosmicbandito at 10:05 AM on July 19, 2005

Testing the PSU:
(1) On many machines, when you plug the power cord into the PSU the PSU fan will spin for a couple of seconds, and stop. If it does this, the PSU is likely to be okay.

(2) You can test whether an ATX PSU switches on (when plugged into power) by unplugging it from the motherboard and shorting the green wire to any of the black (that is, ground) wires. If it turns on, obviously, the PSU is fine.
posted by coriolisdave at 3:12 PM on July 19, 2005