The system ran fine for some time, but then I started having issues when starting up - “USB device over current status detected. System will shut down after 15 seconds”. In these situation, I can no longer start up at all, I have to let the system sit for a couple of hours and then everything works fine again.
This is what I tried to fix it:
disconnecting ALL USB devices,
inspecting all USB ports for bent pins / physical damage,
disconnecting everything from the motherboard except the power cables (so the front USB panel was disconnected, among other things),
manually disabling individual USB ports in the BIOS,
different BIOS versions / resetting the BIOS / removing the CMOS battery.
I was at my wit’s end, when, as my last resort, I tried running my system outside the case. Looks like this:
The system has been stable for several weeks now. So I guess something was wrong in how I fitted the motherboard into the case, I am just not sure what!?
Do you have any advice for me? What should I be paying special attention to when putting it back together? This is what the case looks like:
Since you’ve already tried disconnecting all the cables, the only other thing I’ve ever run across is the motherboard stand-offs in the wrong places causing problems.
I think Dave’s likely right on this, and this should be relatively easy to test.
Once you assembled it outside the case, do you still have it hooked up to the case front panel and USB connectors? It doesn’t look like it from the photos. I would try, if you can get the cables to reach, reconnecting first just the power switch, then the other front panel connectors except for the USB, and then finally any case-based USB connectors. Depending on when you get the error message, you should be able to narrow down the likely cause. My guess is that there’s a short somewhere in the case cabling or connectors, and that this short is the source of your problems.
(It could be that you had something connected to those USB connectors that was the problem, but based on your description of still having the problem after disconnecting all the USB devices and interior USB cabling, my suspicion is that it’s a short on the front panel cabling or connectors inside the case).
If you still can’t replicate the problem after reconnecting the front panel and USB connectors, then you’re likely looking at a problem caused by either stand offs (too many or too few, or the wrong locations – make sure there isn’t a stand off under the motherboard that doesn’t line up with a screw hole!) or screws (I’ve had screws that were too big and have caused minor shorts as they bridged connections on the motherboard).
I think I can rule out the case cabling or connectors as cause of the problem. When the mainboard was still inside the case, I disconnected the front panel USB connectors (8 and 9 on the mainboard layout below) as well as the system panel header (16 below). To power up the system, I simply used a screwdriver. I also disconnected all chassis fans. That way, there was no cable or wiring connection between the motherboard and the case (unless I missed something).
That’s another hassle: since the error message does not reliably trigger on every startup, I have to test each configuration for a week or so, until I can be certain. I thought I had fixed the problem several times already, only to be disappointed several days later.
I guess that’s really it, then, though I find that difficult to imagine. The motherboard has nine screw locations (circled in red, above). I have used eight (!) screws as indicated by the case manual (see below). The standoff in the middle of the motherboard / case is a little different from the others and does not require a screw. I have read that several cases do this, though. Is this a likely culprit then!? I can take a photo of the standoff tomorrow, right now it’s too dark…
I have also double-checked that I have used the case-provided 6#32 screws as indicated by the case manual. You think it’s worthwhile replacing those? I remember that I also tried loosening the screws a bit, back when the board was still in the case.
It’s hard to say, but I think that this is your most likely (although not terribly likely) culprit. I would think it’s more likely that there’s a problem with the motherboard, but if it’s working fine outside the case, then the problem is likely linked to the case – and your disconnecting everything case-related with the motherboard in the case removes the front panel and USB connectors as probable causes. That really just leaves a short circuit or extra current that only happens when the motherboard is mounted in the case, which doesn’t leave much aside from the standoffs (or, more specifically, the area under the motherboard). I would double check that there aren’t any extra standoffs mounted in the case, and that there’s no other debris or metal bits that might be touching the motherboard.
Very weird.
Also, while this doesn’t make sense to me, is it possible the issue comes from the motherboard being in the vertical position, and taking it out of the case/putting it horizontal relieved stress on the motherboard from the cooler or GPU? Maybe try re-mounting it and putting the case horizontal for a week and see if that “resolves” the issue?
Here’s a picture of the integrated I/O shield. Since it’s integrated, the problem should occur regardless of the mainboard’s position inside or outside the case, correct!?
You also get a glance at the different USB ports. They all looked fine to me, but I’ve never seen a damaged or bent one first-hand, so I was a bit unsure of what to look for.
Here’s a picture of the ‘special’ standoff in the middle. I hadn’t seen something like this before, but it looks fine to me, so do the other standoffs.
I had a silver bit thingy and did not know its use (as it is not listed in the manual). I now realize that it neatly fits the standoffs and allows for unscrewing them from the case. Would you guys suggest mounting the mainboard with fewer standoffs, just as a test? The annoying thing would be that it’s a pain to readjust later on, as you have to take everything out again…
