I had posted this in another thread, but I'm starting this one so as not to hijack the other OP.
I recently finished a new build with an M8 Gene, and it posted on the first try. Installed Windows 10 from USB. Installed drivers. Updated Windows. Enabled XMP profile in BIOS. Started downloading and installing software.
After about 90 minutes of continued, uneventful use, the machine suddenly rebooted, but didn't post, displaying "00". After a few seconds, it spontaneously restarted, this time booting all the way into Windows. About 20 minutes later, the same cycle: turn off, restart (no post), restart by itself, successful boot. This happened 3 or 4 more times, and then it shut down and stayed off.
I turned off the PSU for a couple of minutes, restarted, everything normal again, until the reboot cycle started all over. Eventually, recycling the PSU didn't fix it any more: now the mobo leds turn on but the fans don't spin, and I'm stuck at Qcode 00.
I reseated every connector, every DIMM, and the GPU, no change. I swapped the PSU for an identical unit I had for my next system, no change.
The system was working fine, then it slowly degraded until it no longer posts.
Today I removed all DIMMs, and started testing with one at a time. Every time, the system posted to the UEFI, then, after varying amounts of time, restarted to code 00. When I added a second stick, the post would start, but it would restart just before loading the UEFI. I then installed all four sticks, and I can't get anything but an instant 00, leds on, fans not spinning, except for CPU (the pump) and CPU_OPT (a rad fan), which do spin..
Right now I am updating the BIOS to the latest version, but I'm not too confident this will solve the problem. I won't be happy if I have to dismantle the system to troubleshoot the CPU, because it's a hardline build in a small case, and ithere is no easy way to drain it, so taking it apart would be a major pita.
CPU: core i5 6500
RAM: 16 GB (4x4 GB) Corsair Vengeance 2400
GPU: EVGA 980 TI SC
PSU: Seasonic 1050XM
Storage: Samsung 950 Pro m.2
Cooling: D5 pump in EK Revo Xres top, EK monoblock, EK FC block and backplate for the GPU, EK rads, Vardar fans
The system was extensively leak tested, first with air pressure and then wirh an external PSU, before powering up. I'm confident I have no leaks.
EDIT: I assume the BIOS update worked, but I haven't been able to verify it. As soon as I switch on, I get 00, with any number or combination of ram sticks. At least I know by now that the RAM is not the problem. The PSU has also been eliminated, because the situation is identical with two separate PSUs. If I understand correctly, this leaves either the mobo or the CPU as culprits. I guess I will have to tear the system apart after all, because neither can be replaced without starting over. I'm still puzzled that it worked fine for a while and then just decayed. Any ideas???