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Weird hardware problem

Last week I shut down my P4 system (which had been running for a few months). Went out of town for a week, came home, hit the power switch and... nothing.

No whirr, no HF spike, no video, nothing. It's like it's not plugged in.

Power's good to the PS, but nothing on the power switch.

Any ideas what to check first? Can a PS just "die" inert like that?

Philo

Philo
Sunday, July 11, 2004

Yup.  Happened to me a couple years ago.  Machine was off for about a week, turned it on, PS was dead.

free(malloc(-1))
Sunday, July 11, 2004

Loose connection somewhere.  My first thought would be the connection between the power supply and the power switch.  That could've gone out months ago.  After that I'd try the connection to the motherboard.


Sunday, July 11, 2004

Something very similar happened to me recently.  Normally, we never switch the machine off at the wall.  But, one day we did.  When we switched it back on, it was as if it had forgotten how to wake up again.  The "on" switch just didn't do anything.  They replaced the power supply under warranty and now its fine.

John Rusk
Sunday, July 11, 2004

My modem did that.

Was Working fine, moved house, plugged it back in and it never worked again.

Aussie Chick
Sunday, July 11, 2004

Aussie -

That's referred to as the "10 foot" theorem.

It states that any piece of previously functional hardware -- be it a drive, an entire system, a modem, whatever... will cease to function forever when moved 10 feet or more from the location in which it was previously functional.

Corrollary - in some cases the hardware can be made to function again by replacing it in its original location.

muppet from forums.madebymonkeys.net
Sunday, July 11, 2004

If your cdrom and hard drive does it's boot up initialization spins, but you don't get your happy BIOS beeps it could be the capacitor on the motherboard. I had one system die that way. The capcitors from 2002 is suspect because of a capacitor formula scandal in asia.

Li-fan Chen
Sunday, July 11, 2004

One day my monitor wouldn't turn on.  It was just dead.  So I went out and bought a new one and gave the old one to my wife's brother who "likes to fool around with electronic stuff".

One day he calls me up and says that it was just a bad on/off switch. 

Your Pointy Haired Boss
Sunday, July 11, 2004

The first IT technical tip I ever remember receiving was from my highschool computer science teacher. (we were using the old blue screen macs back then).

He told us never to use the on/off switches on the machine, always switch them off at the wall. His rationalisation being that it was cheaper to fix a powerpoint then it was to fix an on/off switch on a piece of computer hardware.

Aussie Chick
Sunday, July 11, 2004

I had a similar experience once a long time ago when ATX power supplies were very new. I ended up resetting the BIOS settings using the little red jumper, and then everything started working again.

Hardware is voodoo stuff!  If you ever flip through datasheets for electronic parts, and observe the amount of assumptions and complexity of how things are supposed to work, you'd be scared to touch any on/off button..  :)

techno dude
Sunday, July 11, 2004

Is the PS circuit breaker set to "on"? ;)

Jimmy Jo-jo
Monday, July 12, 2004

Do you hear the power supply fan whirring? Do you see any hard disk activity lights?

If the power supply fan is out then chances are you have a blown fuse (or something more serious).  If you see hard disk activity (or network activity) lights then chances are your video cable has come loose or if you are using one of those KVM thingies it has switched to some other inactive port!

And as strange as this may sound...I have a old DELL which does the same thing...for some reason it refuses to power cycle unless I when I remove the power supply plug from the back of the machine...wait for a couple of mins and then reseat it.

Code Monkey
Monday, July 12, 2004

My old K6 did that *every* time. Solution was simple, yank the cord out of the PS, count to 3, plug back. Counting to 3 was *very* important.

I think it was the capacitor.

(The flux capacitor, that is.)

Alex
Monday, July 12, 2004


If it was the flux capacitor, why did you have to count to 3?

Why could you just send it back in time 3 seconds and get zero downtime?

Talk about parallel computing...

KC
Monday, July 12, 2004

Unplug the power supply - hold down the power switch for 30 seconds or so, and then plug it back in.  I had a newer power supply that would forget how to turn itself back after it was shut down a certain way.  Unplugging it and getting it to use up the charge in the capacitors would reset it and get it going again. 

Probably not what's going on here, but it's an easy check.

Unfocused Focused
Monday, July 12, 2004

Whoa - that did it! Unplug, hold the power switch in for 30 seconds, plug back in, hit the switch, and it came right up!

Bizarre.

Thank you very much!

Philo

Philo
Monday, July 12, 2004

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