Computer has trouble powering on

[zylander]

Recently my computer has been having trouble powering on. If I push the power button, the green power light flashes once and nothing happens. The second time I push the power button both lights flash once and the computer will turn on for a fraction of a second, all the fans twitch a little bit, then nothing happens. If I hold down the power button, it goes through about 5 or 6 of these cycles and then finally fully powers on.

I thought maybe there is a problem with the button on the case so I tried jumping the puns on the mobo that the button connects to and the same thing happened. My mobo also has a power button on it but the same thing happens when I use that too. There are no loose connections anywhere, any ideas?


edit: also, once the computer is on, it runs fine and will stay on for as long as I need it to.


system specs:

DFI Ultra-D motherboard
AMD Opteron 165 s939
7900gt
Antec Neo Power 480w

 

[robisbell]

full system spec please.
Motherboard Manufacturer with Model and BIOS Revision:
CPU Manufacturer and Model:
RAM Manufacturer and Model:
PSU Manufacturer and Model:
HDD(s): Manufacturer and Model:
CDRW/CDROM/DVD Manufacturer and Model:
Video Card: Manufacturer and Model:

 

[Fardringle]

I worked on a machine a while ago with almost exactly the same problem. This one would turn on but produced extremely bad graphics artifacts at first. It turned out to be a problem with a bad component in the power supply that didn't function properly when it was cold. Once the power supply was warmed up a bit the computer could be restarted and would work perfectly until it was turned off again. I was even able to get it to boot perfectly the first time by warming up the PSU with a hair dryer before turning it on. Even though the computer did work just fine after the PSU warmed up properly, the owner didn't want to deal with it so he bought a new PSU and hasn't had a problem since then that I am aware of.

This could also be a sign of bad capacitors or other circuitry on the motherboard, so if you do decide to try a new PSU, get one from a place that will accept returns so that you can take it back if it does not resolve the problem.

 

[SerpentRoyal]

Probably a bad PSU.

 

[zylander]

DFI Lanparty nF4 Ultra-D, dont know BIOS.
Opteron 165
OCZ Platinum 2gb DDR400
Antec Neo Power 480w
Maxtor 200gb, WD 250gb, dont know model numbers
Lite On CDRW, Samsung DVDRW and DVDRW-DL, dont know models
EVGA 7900gt

 

[robisbell]

I concur.

 

[RadiclDreamer]

Power supply

 

[oynaz]

It is almost certainly one or more failing capacitors, either in the PSU or on the mobo. I had these exact symptoms a month or two before my previous motherboard died.

 

[zylander]

I had a feeling it could be the PSU, but thought that since it ran fine once it was on, that it wasnt the PSU.

I dont think its the motherboard because this is my second Ultra-D mobo, I replaced the first one because this same problem was happening and I thought it was the motherboard.