Hi all,
I know this issue seems to be something from Ground Hog Day and there are facets of this threads everywhere, however I haven't found a thread where I'm experiencing the same issue.
Hardware:
MOBO: x99-UD4
CPU: i7-5960x
COOLER: Corsair H100i
RAM: Kingston Hyperx 4x4 (16GB) HX430C15PB2K4/16
VIDEO: Matrox M9188 and M9148
SSD
PSU: Thermaltake 750w Toughpower Gold
CASE: Thermaltake Core V71
On very first start up, when I turned on the PSU the system was in standby/ready. I pressed the power button on the case. The machine booted, ran for 5 seconds and then the PSU shutdown the system. There was no loop.
In that 5 seconds all fans and lights powered up, the red LED in the top left corner of the mobo lit up for a second then it all shutdown. The only USB device I had connected was the keyboard and the Corsair cooler on internal USB.
However when I turned off the PSU, waited and then turned it back on, the system automatically booted without using the case power switch. Which leads me to believe the mobo is bridged open.
Troubleshooting:
Stepped through the mobo troubleshooting steps to the letter
Checked F_Panel was plugged in correctly, System still boots when the case isn't connected.
Check RAM for correct slots, tried booting using all four individually in slot DDR4_1_1A and in combinations of two's.
Removed both Video cards, tried them in individually
Removed RAM and Videocards
Disconnected the SSD
Cleared CMOS, left the battery out for great than 10 minutes and all steps again.
Ensured the CPU 12v was connected correctly
Tried a different PSU
Removed everything from the mobo, including CPU, so only main power and 12v CPU power was connected.
Even connected a PS2 keyboard
All of these resulted in the exact same outcome.
Switching on PSU instantly boots, run for 5 seconds, No beep, No POST and No Loop.
I can't flash the bios as the keyboard will not enable, for either the USB or PS2
The only thing I haven't tried is a different video card, but I think I have exhausted all avenues to be left disappointed the mobo has to go.
Any thoughts that I may have missed or haven't tried, I'd be interested to know.