Question Everything Blurry After DVI > HDMI > DVI

[Draehl]

GPU: Gigabyte GTX 970
CPU: Intel i5 4590
Motherboard: Asus Z-97A
RAM: 8 gigs of Corsair- sorry don't have the exact specs on this.
PSU: Corsair RM650
OS: Windows 10 Pro
GPU Drivers: 460.79
Monitor: Samsung s27a950d 120hz

I recently had my PC temporarily hooked up to my downstairs TV via HDMI, just brought it back upstairs re-connected back to my regular DVI monitor and while it's technically displaying everything at 1080p/120hz, and good framerates everything visually looks very poor quality:

• Everything is slightly grainy/lower res looking (images, texts, polygons in games, particle/shader effects, etc. Everything looks very rasterized rather than vector)
• Everything is noticeably dimmer than before- white colors are more of an off-white both on the desktop and in games. YouTube thumbnails and video is noticeably low res/slightly grainy too. This persists even when the drivers are uninstalled.
• In League of Legends for example the text box and text itself is physically smaller than just last week when I had it hooked up to the DVI monitor. I did not even play League while it was hooked up to HDMI. This further makes me think something got buggered with a global DPI/resolution/scaling setting that isn't wiped with the drivers/system restore OR something is stuck on the hardware end.

I had this happen once before with this exact PC just after reconnecting to DVI from HDMI but don't remember the exact fix. If memory serves it had something to do with the GPU thinking it was still on the lower DPI HDMI TV, despite the DPI in windows being fine.

Troubleshooting:

• It's not plugged onto onboard video (first thing I checked!)
• Removed the display adapter in device manager.
• Completely uninstalled all Nvidia software, reinstalled clean after a restart.
• I swapped over to the onboard video and the monitor's brightness is fine there. Monitor's input setting is PC, not AV.
• Tried the other DVI port on the GPU.
• Tried the PC back on the HDMI TV and it looks fine there.
• Unseated the GPU, cleaned everything out.
• Ran system restore back to November before I even moved the PC off the monitor.
• Tried various scaling and resolution settings, no effect. (Nvidia and Windows)

I would very much appreciate any help you could offer. I think something is stuck maybe on the GPU firmware or a software setting unaffected by the driver wipe/system restore- something "thinks" we're still on a lower DPI TV rather than a monitor. As I mentioned above I've had this exact problem in this exact circumstance a couple of years ago and don't think anything is physically broken.