Blurry/Fuzzy text on Windows 8.1

[Knslyr]

Hello
The text on my screen have suddenly become blurry. I've tried adjusting ClearType-text and that didn't change anything.
Also looked into dpiscaling but that didn't seem to help either.
This problem just appeared after I started my PC and I can't remember I've done any such changes at all.
I need some ideas of what to try to get that text sharp and clear again.

PC Specs:
CM Storm Stryker | Asus Z97 Deluxe | i7-4770K@4.3Ghz | Seidon 120V
MSI GTX 970 (2x SLI) | HyperX Fury 1866Mhz 2x8GB
XFX Pro 850W | Crucial M500 SSD 480GB | Seagate Barracuda 2TB

Screen: ASUS ROG SWIFT PG278Q
Resolution: 2560x1440, 144hz

The blurry text is most noticable on the dekstop. The text under the icons.
And also in the top menu in chrome and internet explorer (adressbar, bookmarks, tab titles)

[lockblock]

I wouldn't jump to the conclusion that you have a defective gpu, but it couldn't hurt to try and rule it out.
Try using the 2nd gpu without sli and see if the problem persists.

[Knslyr]

I wouldn't jump to the conclusion that you have a defective gpu, but it couldn't hurt to try and rule it out.
Try using the 2nd gpu without sli and see if the problem persists.

I tried this now. It didn't work Im afraid.
But keep the ideas comming.

[Nuckels]

Run a system restore to before the issue, see if its there.

[Knslyr]

Run a system restore to before the issue, see if its there.

Yeah I think I'll do that during the night if I don't find any other way to fix it.