Here we go again: Was playing FO4 when the system suddenly shut down and went into a reboot loop again, same as before. Only code 15 this time (pre-memory system agent initialization is started). Reseated and tested all RAM and slots, cleared CMOS. Got code 14 then (pre-memory CPU initialization started). Checked CPU and socket; all okay. Removed and reseated mobo and tightened the screws a bit more than before*. Booted just fine. *my crazy theory; maybe the mobo screws weren't tightened enough causing the whole thing to sag just enough to short it, causing the problem? Any ideas what might have caused it, and what I can do if it happens next? I'm not feeling really comfortable now that it might happen again. Edit 1: Well it was fine in Windows, loaded a save game and boom there it goes again. Thoroughly p***ed off now! I've never had PC issues before and now it's something off and on with a single system I cannot reply on. Edit 2: Could only get it working after taking out the entire mobo again but this time I replaced the screws for ones with a slightly wider head for more grip. Then I got code 99 with no display. Had to revert to my old DVI display, enter BIOS after another CMOS reset and save and exit to get my new 144Hz DisplayPort monitor working again. I've been at it for hours and am worried that as soon as I launch a game I'll be back to a boot loop (and I was right). I don't know what else to do I have no extra components to test with nor can I get any. Online searches yielded people with the same thing, always seems to happen during heavy load ie gaming but no one has found a solution. Replacement boards didn't solve it either for them. Am going to flash the newest bios to it shortly and even considered the wall socket being bad so tried another, albeit not grounded, one to no avail. Also, I have my GPU zip tied upwards to counter the sag, could that be it? Grasping at straws now. Edit 3: Because I keep thinking of a short somewhere I removed the side panels (to no avail), reseated all cables in the PSU, removed the top panel and it booted just fine - although I doubt that's the culprit. Here's a pic of the top panel where you can see a ground wire attached to the case, a rolled up LED wire I don't use, and 3 empty sockets from which I removed cables I don't use (front eSATA, USB 2.0 etc.). Could there maybe be a short caused by something faulty with the case that I simply cannot see? I don't want to buy a new case on a whim, hoping that'd solve it.