Computer Boots But No Power to GPU, Mouse, Keyboard

[kmuck81]

So, I recently picked up a new mobo, CPU, and RAM to upgrade my girlfriend's computer. After getting everything put together and reinstalling Windows the computer started exhibiting some odd behavior. Often when it booted it wouldn't send any power to the mouse and keyboard and the graphics card wouldn't send any signal to the TV. After tinkering with the unit some I've mostly eliminated the issue, at least so far that it'll boot, restart, shut down and power back up quite fine at first. However, after hours of usage it starts to exhibit the same problem with booting back up. I really have no idea why it works fine until it's been used for awhile, at which point it starts acting up again.

System specs:

ASRock 990FX Extreme3
FX-6300 (stock settings)
8GB G.Skill Ripjaw 1600mhz
GTX 560 ti
250GB/1TB HDDs (Windows is on the former)
800w Ultra PSU

Things I've tried troubleshooting: Trying a different power supply (another Ultra 600w one, both are quite old), trying different RAM that I know works in different slots on the mobo, trying different cables, updating the bios, reseating the heatsink on the cpu, checking for physical damage on the motherboard, plugging the GPU into a different PCI-e slot.

None of it seems to have made a difference. I guess the next step is to pull my Corsair HX750 out of my gaming rig and try that, since I know it's a reliable power supply, though it seems odd that I'd get that exact same issue from two different power supplies, even if they are both the same brand and older.

Any tips?

 

[MC_K7]

Well you already tried with 2 different PSUs... sure you could try with that Corsair unit because it's higher quality but I don't think the PSU is the problem (unless these 2 Ultra units are defective at the same time which is unlikely).

I'm leaning towards the motherboard. By the way, you don't need to see physical damage on it for it to be defective. Since it's brand new and that it's been acting up since day 1, it's more likely that you got a mobo with some defects from the start. I would ask for an exchange or replacement since it's still under warranty.

 

[kmuck81]

Yeah, that's what I was thinking. Was just hoping beyond hope that I missed something obvious. RMA time it is.