Strange pixel-like artifacts on screen

[Tupples]

I was playing a game when these small squares appeared on my screen, they are numerous and in groups of 4 little pixels. When I move my mouse, they kind of flicker. They also seem to change color depending on the background .
I tried taking the GPU out and running on integrated graphics and they disappeared, so it's not a Windows or CPU issue. Next, I tried reinstalling my GPU drivers to the latest version (I have an MSI R9 390, I was running on the second to latest drivers). The artifacts were still there. I then tried to install an earlier version (catalyst), but that didn't help either. However, when I remove all drivers and just let the Windows basic GPU drivers take over, the dots disappear.
Any thoughts what could be causing this? And how I can fix it? It appeared out of the blue, never had any issues with the card before other than it running pretty hot.

 

[Tupples]

I tried changing PCI-E slot, and it didn't solve the problem. I'm just running without AMD drivers right now since it's quite annoying to have flickering pixels with the drivers installed.

 

[Cody Ramnarine]

check up on the settings inside of the AMD softwares that are installed. I have a 380, havent seen it happen yet

 

[Tupples]

Settings are fine, I have tried messing with them too with no result.
I have also tried underclocking/overclocking the card (Core clock, memory clock and voltage), again didn't do anything.