GPU(s) do not display image.

[DedMop]

I upgraded from a GTX-1080 to a RTX-2080 Super I ordered off Ebay 3 weeks ago. Ever since, at random times, the screen would go black and the PC would reboot. This occurred multiple times. Even when not gaming.

 

So I did multiple tests:

 

TEST 1: Did clean re-install of newest drivers. 

 

TEST 2: Changed PCIE slots.

 

TEST 3: Swapped GPU with a working GTX 770.

 

TEST 4: Replaced PSU cable to the GPU.

 

Tests 1-3 ended with the same results, screen goes black and PC reboots. After Test 4 however, neither GPU displays an image at all. PC comes on fine, no other forms of unusual behavior, the GPU(s) simply won't output to the monitor. 

 

Any help would be appreciated, I dunno where to go from here.

 

SPECS

 

CPU: Xeon E5 1680 V.2

GPU: RTX 2080 Super - EVGA

RAM: 32GB DDR3 1600mhz - Gskill

PSU: 750W [Bronze] - EVGA B5

M/B: ASUS Rampage IV Extreme

MONITOR: ASUS ROG Swift PG279QZ