[SOLVED] X99 Classified Post LED code 37

[Alexoferith]

Hi, I wonder if anyone can help me. About 2hr ago, I switched on my PC, it was booting up surprisingly slow. Once the boot up finished, I try to run msconfig to see if any unwanted software was in the start-up. But nothing happened. The HD LED was very dim but flashing continuously. By the way, the HD LED has different brightness. Anyway, I decided to restart the PC. When it started up, it seemed to be stuck on the X99 CLASSIFIED logo. I then proceeded to switch it off and opened the side panel. I once again switched the PC on. The POST LED was showing different hex codes then stopped on 37. According to the manual, it was initializing the North Bridge. The last thing I did was to change my cup back to stock speed as a suggestion to fix my Steam client software crashing the whole system whenever there was an update to the Steam client software. By the way, the CUP is i7-5930K overclocked from 3.5 to 4.4. It is watercool by an EVGA CLC 240 AIO. CUP temp never went over 70 Celsius. And CUP has been overclocked over a year. It was stressed test using Intel Extreme overclocking software and also MSI Afterburner. 4.4Ghz was the most stable speed.
Full SPEC:
i7-5930K with EVGA SLI 240 AIO
32 Gb Corsair Vengence 2666 RAM
2TB Samsung 850 EVO SSD
EVGA GTX1080Ti FTW3 x 2 in SLi
EVGA Supanova 1300W gold plus PSU
Corsair Graphite 780T case with 2 x 120 fan at front blowing in and 1 x 120 fan extracting (all 3 are Noctua fans).

Edit: I have replaced the PSU with a brand new one. I have also replaced the 8 memory modules with 4 brand new modules occupying slots 1,3,5,7 as indicated in the manual. When I turned on the power supply, the PC immediately start-up without me pressing on/off button!! And then the PC just went off, then on again without me pressing anything! I unplugged the power cable immediately. I checked all cables in the PC and the PSU, all are in properly. I then plugged in the power cable again, it started doing the same thing! I unplugged the power cable again. This time, I pressed and hold the BIOS reset button then I plugged in the power cable. Now nothing happened!!! Any idea? Anyone? Have I blown the lot? Oh dear...

Update1: I am so dumb. I read the manual in more detail. the memory slots are not in logical order as I thought. It is not 12345678. It is 12348765!!! By now, I got myself a new set of memory modules:4 x 8Gb Corsair Vengence 2666 modules and installed them in the correct slot. Now the PC will not start up by itself when it is shut down. However, the PC will not boot up and stuck at POST codes "37". And the PC always gave off 4 or 5 beeps. First 4 beeps were at a lower frequency, then the final one was brighter and slightly higher. The 4 beeps were "long-short-short-short" or "long-short-short-long". The last beep seems to be the same as the beep when switching on any PC. But if it was 5 beeps, then that means that the CPU is faulty. But how to be sure? Anyone has any idea? Many thanks in advance.

Update2: Ok, I adopted the basic way of diagnosing problem, by elimination. I proceeded to test the two 1080Ti by installing them one by one into my daughter's PC. The 1st one, the system couldn't boot up and ever got past the logo screen. With the 2nd one, my daughter's PC booted up fine. I am using it to type this update. I then proceeded to install one of my daughter's graphics cards into my own system. It is a GTX 980 from EVGA as well. Same problem. So, now, my own system has a new CMOS battery, new PSU and new memory modules, so either the CPU or the motherboard has developed a fault, or both of them... Sigh... Any idea, anyone? Is it time to "upgrade"?

 

[Alexoferith]

I guess no one knows. Final update: a new motherboard and a new CPU have replaced the X99 and the 5930K. Also, the first of the 1080Ti is suspected to be faulty as well...