New build: Motherboard powers up once, but not twice

[Mursilis]

I'm swapping out motherboards on my system, and I've put the new one in with a 'barebones' configuration for testing. Parts are:
Motherboard: Gigabyte GA-K8N Pro-SLI
CPU: Athlon X2 3800+
RAM: 1x1GB Patriot DDR
Video: ATI X1900 AIW

Putting it in my case and powering it up, it powers up fine ONCE - lets me go into BIOS, etc., no issues. It detects the CPU, RAM, etc., just fine. However, when I power down, it won't power up again. The only way I can get it to power up again is by unplugging it and letting it sit, or moving the RAM to a different slot, or something like that. Then it's good for ONE more power-up, and again it won't power up after that. Thoughts? I think the case and power supply are not the issue, as both have been flawless with my old board. TIA for any tips/ideas.

 

[MegaVovaN]

How long between power down and power up?

My Abit IP35-E manual says I must wait 30 seconds before powering down and powering up.

 

[Mursilis]

Originally posted by: MegaVovaN
How long between power down and power up?

My Abit IP35-E manual says I must wait 30 seconds before powering down and powering up.

If I do something like move a RAM stick, it will power right back up, but if I do nothing with it, it usually won't power up at all. I can't figure it out at all.

 

[Jiggz]

With a barebone configuration is the mobo properly grounded? It sounds like a capacitor is not discharging to allow the power up circuit to close. If it's properly grounded, it's probably a bad mobo. You can also try manually starting the PSU, while it is plugged into the mobo power connector by shorting the green wire with any of the black wires. Remember do this when the mobo will not power up and without changing anything like unplugging it or switching ram sticks. The test will eliminate the PSU from the equation. If it manually starts after you manually started it, then the mobo is defective. If it did not, then the PSU is either not properly grounded or defective. Goodluck.

 

[Mursilis]

Originally posted by: Jiggz
With a barebone configuration is the mobo properly grounded? It sounds like a capacitor is not discharging to allow the power up circuit to close. If it's properly grounded, it's probably a bad mobo. You can also try manually starting the PSU, while it is plugged into the mobo power connector by shorting the green wire with any of the black wires. Remember do this when the mobo will not power up and without changing anything like unplugging it or switching ram sticks. The test will eliminate the PSU from the equation. If it manually starts after you manually started it, then the mobo is defective. If it did not, then the PSU is either not properly grounded or defective. Goodluck.

Thanks for responding. I tried manually starting the PSU by shorting the wires, and it powered up. What do you mean by grounding the motherboard? Making sure it's screwed into the case? I'm not following you on that.

 

[Jiggz]

Originally posted by: Mursilis

Originally posted by: Jiggz
With a barebone configuration is the mobo properly grounded? It sounds like a capacitor is not discharging to allow the power up circuit to close. If it's properly grounded, it's probably a bad mobo. You can also try manually starting the PSU, while it is plugged into the mobo power connector by shorting the green wire with any of the black wires. Remember do this when the mobo will not power up and without changing anything like unplugging it or switching ram sticks. The test will eliminate the PSU from the equation. If it manually starts after you manually started it, then the mobo is defective. If it did not, then the PSU is either not properly grounded or defective. Goodluck.

Thanks for responding. I tried manually starting the PSU by shorting the wires, and it powered up. What do you mean by grounding the motherboard? Making sure it's screwed into the case? I'm not following you on that.

So the part that is not actuating to power up the unit is the mobo. Mobo's have mounting holes which are surrounded or rimmed with conductive metals and some are just plain holes. The rimmed holes are designed for grounding the mobo to the casing. To do this, you will use the brass stand offs with screws to mount it to the case, which provides proper grounding for the mobo. The plain mounting holes can use either the plastic stand offs or brass stand offs. If you already have this set up on your mobo, most likely the mobo is defective and needs to be RMA'd. Another thing you can try is powering up the mobo using a flat tip screw driver to short the two pins where the case's power button switch is connected. However, usually this technique is use to isolate if the power button switch is defective or not. Remember, you should only try the manual powering when the mobo will not boot the normal way or thru the power on switch from the case.

 

[mizzou]

you know how you have all of those HDD LED / PWR / SPKR / RESET connections that plug into the MOBO?

Unplug them all except PWR and then see if the same problem happens.

One time I accidentally had the Reset button hooked to the HDD Button and it would make it randomly quit on me.

 

[Mursilis]

Thanks to all who offered replies. I swapped out the PSU, and the problem went away. I still don't know what was bad about the old power supply, but at least the problem's solved.