What does this problem sound like to you?

[SaevusMalus]

System:
E6600
Asus P5W DH Deluxe
2Gb Corsair ddr2-800
PSU: OCZ 600W
Zalman 9700
Lian Li PC-65B Case

Ok, I have a strange hiccup in the system when I turn it on, but only sometimes. When I hit the power button on the front of the case, everything lights up, starts to power up, then shuts off, just goes dead like I turned it off, but the power light on the mobo stays green (or as far as I can tell, since I can't replicate the problem reliably, hard to watch everything at once, every powerup)
The PSU, according to every meter I can put on it and all my diag tools is putting out constant power, reliable, uninterupted. I thought maybe there was a short in the PSU itself, checked all the cables, all the screws, everything seems to be in place. All my cables are tight (rechecking them right now just ot be sure) The thing is, the system runs fine 99% of the time, it is just once in a while that as I hit the power button, it just runs up for maybe 5 seconds and then kaputs. Hit the button again, comes up normally.
This is just driving me nuts because it reminds me of my car, as soon as I find one problem, no matter how tiny, I know more are on the way.

I could really use a hand, if you have any ideas on what might cause it, or what more I could check, please, let me know. In the mean time, I will keep checking all my connections. Thanks.

 

[buzz_X]

Hi,

Sounds more like a power rugulation issue with your motherboard. Check all connections leading to/from the power supply.

 

[halbhh]

Some good tips above, also I had this kind of thing once where my motherboard was detecting a case intrusion somehow, and putting the side panel back on fixed that, but that's just one possibility. If the motherboard is a type that has any kind of indicator lights or numbers, it might give you a code there.

 

[Ls3D]

Could your power button be sticking? Internally..

Mine sometimes double signals when I'm trying to put her to sleep forcing me to wait for wake up and try again.

-S

 

[redwing]

The power button is connected to a simple de-bouncing circuit that shorts 2 pins on your mobo for a short time. It's possible that there's an intermittent problem with that. If none of the above advice helps with the fix, just something to investigate.

 

[praeses]

Another possibility is that your power button is getting stuck either at the electrical contacts (inside the switch) or perhaps the button is rubbing against the cases.

Turn on your computer and hold the button in, does it have the same effect as the symptoms described?

I cannot remember that specific motherboard's bios (don't have one offhand) but a few have the option of what to do when you press the power button, and some when you press and hold it for 4 seconds (although you stated 5, there is a bit of a delay while posting before those 4 seconds come into play). That may help depending on the options to narrow it down while in regular use.

Lastly, just borrow a reset or power switch (N/O, not N/C) from another computer for awhile and see if the problem persists. A little sanding or oil may all be what's needed.

Edit: Hah, seems like the posters above me beat me to the punch, serves me right for posting while at work ^_^;;

 

[SaevusMalus]

Thanks all, great things to check. I ran Memtest, no problems there, all my connectors are as snug as possible, power seems good, so at this point I am leaning towards a switch problem, gonne try to play with that while. Thanks again folks!