Dying graphics card

[Slaxc]

I built my PC around 2 months ago and everything was great. I had the dell s2417dg and it had decently noticeable color banding but nothing absolutely horrible. It bugged me so I got a replacement for it. When the second one came in it was worse than the 1st but again, not terrible. I decided to plug both of them in via DP to see which was better. After doing this I started to notice some horrible horrible issues. Both of the monitors now looked almost identically bad and they were BAD. https://imgur.com/a/7Gcox this is just a few examples of the problem. I thought it was color banding at first so I returned both of them and yesterday ordered a PG279Q. After talking to some people I realized it's a GPU problem and nothing to due with the actual monitor. I have no idea what to do or how to fix it. Another thing thats happening is my PC will suddenly crash and the graphics card starts flashing. It's a ASUS Strix GTX 1080 btw. It'll just keep flashing white and I have to manually hold the power button and turn it off and back on. It does this quite a bit which seriously frustrates me but hasnt been doing it as much as it used to. Another thing to note is upon turning on the PC all 4 POST LED's light up on my motherboard. This includes CPU, DRAM, VGA, and BOOT. I've tried doing everything to fix this, reset CMOS, check cables, etc. but it still happens.

If anyone has anything that could help please let me know. Thanks a ton.

[Kewaninou]

I don’t know a lot about this problem but maybe this can help. Did you try plugging your GPU into a different PCI-E slot, maybe that PCI-E slot is dead.

Hope I could help