Cannot resolve black screen issues

[flatearther]

This is long so bare with me, the short version is below. I am running an XFX HD 5770 (don't laugh) and it has served me well (I'm hoping the misses will get me a 1060 for Christmas). Anyways I decided to redo the TIM on my CPU because I was running warmer at idle with an H100i. Everything goes as planned until I restart and get a black screen. The monitor's led is blue and getting a signal but the screen is black no back light either. Next I swapped from the HDMI port on to the DVI port on the GPU still black. Then went to the bios and verified the display is set to PCIe, booted into safe mode and checked saw the Intel graphics were enabled as well so I disabled them. I booted back to normal mode still the same black screen. Next I booted back into safe mode and ran DDU to uninstall the AMD drivers. After a reboot I have video from the GPU with the basic drivers. When I go to install AMD Catalyst legacy drivers that I know work I get a black screen during the install that never recovers. I waited an hour after the install before I did a reset still the same. Back into safe mode GPU-z shows the card is reading on the x16_1 slot and the driver version is correct. I have tried reseting all PSU connections to mobo and GPU, running one stick of ram and only the boot drive. Still no joy.

Here where I am confused. Trying to rule out hardware or software I shut down the PC and moved the GPU to the second PCIe x16 slot and it works with the AMD drivers. So then knowing the card and driver is working I moved back to the first slot, Still had a black screen. Went through the process again of DDU uninstalling, removing old drivers from C:\AMD\ restarting etc. Now this time whenever I try to run Catalyst, Crimson Beta, or Crimson Minimal the pc freezes during the "Analyzing System" and I have to do a hard reboot. Im going to try cleaning the registry tonight and if that fails do a fresh OS install as a last resort. Also had one BSOD during Catalyst install minidump pointed to atikmdg and watchdog. I can post the dump file tonight.

Could I have a dead PCIe slot even though it runs using basic drivers and GPU-z recognizes the card? I dont have quick access to another card at the moment.

Short Version
Redid CPU TIM now GPU black screen only on top PCIe slot with drivers installed. GPU works on second PCIe slot with drivers. NOW Catalyst freezes during install. Trying to determine if PCIe slot is dead or driver issue before Santa bring me a new card.

Tried:
Reseating Card
Verifying PSU voltage via multimeter
Running only CPU, cooler, GPU, 1 8GB ddr3, and boot drive
Compressed air in PCIe slot
DDU uninstall old drivers
Reflashed bios and updated chipset drivers and firmware
Different cables on different ports from the GPU
Different monitor
Disabled Malwarebytes and Defender


System
ASUS P8z77v Pro MoBo
Intel i7-3770k CPU
Corsair Vengeance 32GB Ram (8GB*4 DDR3)
Samsung 840 Pro SSD boot drive
2 Seagate 7200 rpm 1.5TB HDD's
XFX Radeon HD 5770 GPU
Corsair CX 500w PSU

 

[flatearther]

I found the issue. It was a single bent pin on the CPU socket. I lined it back up and it seemed to have fixed my PCIe slot.