Random Screen Flickering and Static

[okkee]

Background

Beginning of the year I got an old optiplex 3020 and a rx 570 which i connected using a sata to pcie cable. This worked just fine for a couple of months. The only problems would occur during a power spike and i'd see static or the PC would just crash with the fans on full blast. But I was able to use the PC and play games just fine. So i eventually got a b85 motherboard and a PSU because the dell board had some audio problems and i wanted the higher wattage. This put the dell parts (board, fan) into storage. A couple of weeks ago I got a new CPU and decided to cobble together a PC for my sibling using the optiplex parts and some parts from an old HP 500MT. So its essentially the same system I was using earlier this year.

 

The Problem

However, now there's this random screen flickering which can go on for about a minute coupled with these random static images. I'm about to DDU and re-install the drivers but I believe it's either the lack of proper power or the card is in its last days in which case the best i can do is get it cleaned and repasted. I just wanna ask if there's anything else i might be overlooking.