Gigabyte X79-UD5: power on, power off...

Redshirt #24

Jan 29, 2006
This UD5 I bought about a month ago does one extremely annoying thing: it randomly (usually when waking it up from sleep, but sometimes on a cold boot) will go into a loop where it powers on and off at about fifteen second intervals without ever making it to POST. Powering it off fully for about a minute will allow it to POST and boot normally, and it's generally fine once it boots (there's the odd lockup in Windows, but that's Windows).

From what little I've been able to find about this issue, it hints at it being either a motherboard or RAM by process of elimination I've

1. removed two of the four 4GB sticks of Corsair Vengeance DDR3 I was using;
2. updated the backup BIOS to F10 (and just recently updated the main BIOS to F12);
3. removed the CMOS battery entirely for about four hours to clear it, and left all CPU/memory/voltage settings the hell alone afterwards; and
3. replaced the RAM entirely with 16GB of Samsung LP DDR3, though it's apparently chugging along at 1.5v like the Corsair DDR3 was

all to no avail. I'm going to be swapping out the power supply for a 1000w I bought from matrix563 immediately after posting this, just to be absolutely sure that's not somehow messing things up, but am I likely right in assuming that the board is just plain screwed in the head?
Didn't GB boards have boot loop issues on P67/Z68 as well? Sucks to hear it is happening again for some users. Sorry I can't provide any help, other than to say that unless your PSU is faulty, it is easily even to power your rig.
sounds related to overclocking. might want to try upping the juice a little.
I think this is the board you got from me. I never experienced this issue while i had it, so there must be a difference in the configuration that is causing it.

Try setting ram to XMP and then bump teh voltage up from whatever spec is. EG if spec is 1.5v set it to 1.55V.
If I'm reading your specs correctly, you're running a GTX 690 with a 750watt PSU. If that's the case, the PSU very well could be your problem.

Then again, X79 boards do strange things for some reason, my ASUS RIVE misbehaves on occasion as well.

If the bigger PSU doesn't do the trick, try RMAing the MB
If I'm reading your specs correctly, you're running a GTX 690 with a 750watt PSU. If that's the case, the PSU very well could be your problem.

Then again, X79 boards do strange things for some reason, my ASUS RIVE misbehaves on occasion as well.

If the bigger PSU doesn't do the trick, try RMAing the MB

You really should be running a 1200 watt PSU on that rig

Please stop giving advice like this, a 3930K + 690 + H100 and a few drives, all heavily overclocked, would draw maybe 600W at 100% peak if you ran LinX and a max GPU load. 1250W would maybe be appropriate for 4X 680 Lightnings with overvoltage. Gaming load on his rig is under 600W, probably closer to 550W.

Evidence: 3960X @ 4.3GHz = 515-550W
Update: I couldn't get the UD5 to even POST with the 1000W PSU in my HAF X--it actually did an even faster power loop. I was afraid it was somehow shorting out, but reconnecting the 750W both in and out of the case brought it right up. That said, the 1000W is now in an extremely basic Antec case from 2006 powering a 2600K and Z68 motherboard (and my original Corsair DDR3, all 16GB of it) without any obvious at a basic level it's clear.

(Sidebar: I'm not overclocking a damn thing in the rig as is. I'm just amazed the boot loops haven't killed anything in it.)

Barring some sort of truly wacky grounding issue in the HAF X...I suspect I'm going motherboard shopping in the morning. :(
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haha now leave me some heatware :p. :D. maybe the coolermaster cycled faster cause its circuits detected something wrong faster ;). did you try reseating the cpu or checking to make sure goop isn't somewhere around the socket etc or on the board and its grounding it out? or maybe your water cooling spilled a drop or caused condensation somehow (doubt it who knows).
I'll Heat you in a minute, geez. :p

If I had another suitably large case I'd move the core parts to it just to make absolutely sure it wasn't some sort of grounding issue, but if that was the case odds are it would have started doing it with the 750W. So at this point the UD5 for whatever reason doesn't like the 1000W, but a nearby Z68 motherboard does; it's okay with the 750W, but still power-loops when waking up.
motherboards are finicky. my p67 board likes to power back on if it does anything besides shutdown, like sleep or hibernate. don't know why :p. both p67s did (identical boards go figure). different psu's too. oh well
There is someone else having issues with a sabretooth x79. apparently it could be a power supply incompatibility.
I used that board with an OCZ ZT 750W when i had it. The different behaviour with a different PSU may indicate that this is teh root cause.
That makes sense with the 1000W considering what it did, but then we're back to the original issue. If the 750W was going downhill (and in fairness it's been in use for over three years now), I suspect it'd be doing something more frequently and/or obvious than this waking-from-sleep thing. There's still a chance it could be that, though the only way to be certain there would be with a third PSU--and I'm not sure I'm that crazy, since the alternative would be to get another motherboard anyway.

Annoyingly, I've seen just enough curious boot-loop reports on other X79 motherboards (albeit the majority seemingly being Gigabyte) that I'm wondering if this was just a luck-of-the-draw thing and something happened when it went into the rig.
I must admit that i have seen more power supply compatibility issues lately than i would have beleived possible. I have seen vid cards that wont register in the MB bios if the wrong PSU is used.
So it seems feasible to me that this could be it. if you really thing its a case mounting issue, just put it on the bench and see what happens.

Are you otherwise happy with teh performance? And have you tried other sleep modes if they are available?
When it works, it's just dandy. I probably should try S1 just for kicks.

That said, though, it does do one other thing I find very strange: the POST screen only displays the AMI logo, with no status updates or any other text. Three different BIOS versions and it's always done that, and I know I can't blame that on power...
I think I've figured out the why behind the S3 issue, though it's not making me happy: there appears to be a bent pin in the CPU socket, possibly two. No idea if it was like that from the jump--I had to compare it to another board to be certain, since my eyesight is a bit wonky right now. I'm kind of shocked that's all it was doing under the circumstances (okay, and the occasional lockup in Windows, but that's Windows), but at least everything (so far) seems to be just fine stuck on a different X79 board.