admaster99 :
Thanks for the response "SinxarKnights" but I have seen from multiple sources that vsync must be enabled for gsync to work. If I disable vsync I get terrible screen tearing with gsync enabled. But if I enable gsync + vsync at the same time games seem to play like they would with just vsync on. I'm starting to believe gsync is a huge waste of time and money not impressed.
Source:
https://www.reddit.com/r/nvidia/comments/3ne6lg/gsync_tearing_with_vsync_off/ "I've confirmed with ManualG and My friends at EVGA that as of right now in order for Gsync to work Vsync must be enabled. Turning off Vsync with disable Gsync."
I don't have GSYNC, but if you actually DO have to have VSYNC ON for GSync to work, they would not be on at the same time.
*It's 100% true that VSYNC and GSYNC can not function at the same time. No if, ands or buts.
VSYNC would kick in any time you output more than a specific FPS (whatever your max is). GSYNC would work any time below that.
So...
1) I'm sorry that GSYNC doesn't appear to be working, though I'm not sure how to help at this point.
2) Note that it's a 4K monitor thus limited to 60Hz. GSYNC range is below 60FPS. Any time you output 60FPS or higher you default to VSYNC ON. I may have said that already.
As per the video, there really should be no reason for GSYNC to perform worse than VSYNC ON so I'm confused on that:
a) if outputting at least 60FPS both scenarios should be the same (VSYNC ON)
b) if dropping below 60FPS with GSYNC OFF, but VSYNC ON you should get judder (quick stutter)
c) if dropping below 60FPS with GSYNC OFF, and VSYNC OFF you should get screen tearing
d) if dropping below 60FPS with GSYNC ON, game play should remain fairly smooth with no screen tearing. You could s till get stuttering as GSYNC if the FPS is really low, but it shouldn't be low if it's normally fine with VSYNC ON (GSYNC OFF).
3) DDU is worth trying as suggested. I doubt reinstalling Windows will help.
4) The ONLY thing I can think of is that the monitor's GSYNC module is somehow defective.
5) Any way to test with another compatible PC?
*How GSYNC works:
Normal monitors refresh the screen at a set interval. For 60Hz monitors that's every 1/60th of a second. This is problematic if the GPU is a bit late updating the FRAMEBUFFER. If VSYNC is OFF you end up with screen tearing because part of the image gets updated and part does not.
With VSYNC ON you force the monitor to grab the new frame only during a very short time within that 1/60th of a second. It then draws the new frame. The main drawback is it makes things a bit more sluggish because the frame has to be buffered and sit there until the monitor can grab it and draw it.
Another issue with VSYNC ON is that if you can't output at least 60FPS (for 60Hz monitor) from the GPU then you miss the next refresh cycle. Over the period of a second you'll get a mixture of 1/60th, 2/60th, and possibly higher times for each frame. This causes a JUDDER (quick stutter) effect.
Thus, GSYNC->
The GPU outputs its frame as soon as it can be processed then a very short time later the GSYNC module gets it and the monitor draws it. The GPU can take slightly longer to process the next frame, but when done it still takes the same amount of time to draw it. So it's like drawing a picture and handing it to your friend to look at. You may vary how long it takes to draw your pictures but your friend grabs it and looks at it in the same amount of time.
If you haven't forced a CAP (which is possible) the FRAME TIME will be different every single time but the experience is quite smooth.
Why can't VSYNC be ON at the same time as GSYNC?
As I said, VSYNC is for when the monitor is updating at a preset interval. We call this SYNCHRONOUS. Again, the GPU creates a frame, this sits in a buffer, then the monitor grabs it during a very short window.
GSYNC again is when the GPU creates a frame and the monitor draws it a very short time later. The time between frames is different every time. This is called ASYNCHRONOUS. Not synchronized.