Computer won't do anything

[Dr Rosenrosen]

Hi there-
I've had a strange experience where something will happen to my PC with the power...either a surge, faliure, or my wife will accidentlaly unplug it while it's running.

Then, when I attempt to simply power it on, it does NOTHING. No fan....no light...no nothing. However, maybe 4 days later it'll start up if I randomly try it. I've cracked the case to see if antyhing got blown out, but nothing. It simply starts up fine with no sign of errors or anything. Again, it's usually when the power just gets cut altogether while it's on.

Any ideas what the heck is going on? My power supply is fine as I had it checked out. How can I get it started again? I have a major presentation I need to work on this weekend for my thesis. Yikes!

 

[Cybelex]

There is usually an LED on the board that lets you know when the board is powered. See if it is on the next time it won't start.

 

[Dr Rosenrosen]

Hi there-
Nothing is on. I don't see any lights. I just tried it in a different outlet. No luck. But lke I said, it will probably start up in a few days?!

 

[Cybelex]

It's possible that you don't have the LED, so that alone is not definitive. You'll have to check if you see one when it runs.

Check any switches on the power supply. If there is an on/off switch, toggle it a few times. If there is a small slider to choose between 110 and 220 volts, use a small screwdriver or other tool to slide it back and forth. Try a different power cord.

How about the power "switch" itself? Normally, power does not actually flow through that switch to power the machine since it is a momentary switch that just pulses the board electronics to start up. Check the connections where the switches and LED's attach to the board and make sure they are all tight (usually in the corner of the board with maybe a dozen or so connection posts). If you are inclined, you can also determine which 2 posts are connected to the power switch and try starting the machine by momentarily shorting them (only if you feel the skills ).)

 

[Dr Rosenrosen]

So I pulled the case and looked at the board. Everything looks good. Howver, like a *******, I pulled a few plugs off accidentally (mainly from the "JFB2" area of the board). I found the manual online and hooked everything back up. I'm wondering though, does it matter whether the text of the plug is up or down? For example, one of the plugs says HDD LED, and I can't remember if the text on the plug was up or rotated 180 deg where the text faced the bottom of the shell. Does it matter?

In the meantime, I'll just let it sit for a few days. It might just start up before the week is over.

One final question....Can I disconnect the power button, and, use the I/O button on the back of the machine as my power button instead?

 

[Cybelex]

It doesn't matter how the plug is so long as it is pushed onto the pin.

No, you can't use the back switch. As I mentioned before, the front switch does not carry the power to the board, but only serves as a momentary switch to gate the power to the board. So the actual "switch" to turn on the machine is electronic and can't be replaced by an electrical switch.

But your problem certainly looks to be a bad connection somewhere. Make sure all the connections are tight and check that the board is secured to the case and not shorted anywhere.

 

[InsaneVr6]

I had the same problem and I fixed it by reconnecting my physical power button on the front of my tower. Little things like that drive me nuts. I took the whole computer apart just to see if I had a loose connection and I was on the verge of throwing it out because nothing happened!

Does the CPU fan spin at all when you plug the power chord in?

Make sure that all of the screws for your motherboard are there and tight, make sure the power supply is mounted correctly and make sure that the power supply is connected to the right hardware.

If all of these things are done then it has to be a hardware issue.

 

[Dr Rosenrosen]

Thanks for all the tips guys. I'll see what I can find out. Much appreciated!