I am working on a compilation of info to put into a guide for using NVIDIA CP to achieve refresh rate and Downsample overclocks. I have used NVIDIA control panel custom resolutions for several TVs/monitors. However, none of the previous panels would successfully overclock refresh rates. So now that I have a TV that does accept refresh overclocks, I have a few issues that I've never encountered before. Here goes:
1. Games by default, use a 60hz refresh rate.
In order to solve the issue (according to the intrawebs), a custom resolution can be made (say 1280x721) with only a 120hz refresh rate, to force games to default to that custom resolution's only available refresh rate. My problem is that if a custom resolution doesn't have a 60hz refresh rate present, the resolution will only be available in the NVIDIA control panel and not in Windows 8 (not 8.1, I'm avoiding that for now). So if a custom resolution of 2560x1440@100hz is made, it won't show up in Windows Change Resolution screen, thus not being visible to any games. (according to the CRU thread this bug could be an issue with GeForce Experience being installed, which was auto installed by NVIDIA with the 331.xx driver update; however it was uninstalled, and drivers changed several times all the way back to 306.xx, always with "Perform a clean installation" checked; which according to ToastyX should have fixed the issue.) However, if another custom resolution of 2560x1440@60hz is added via NVCP, 2560x1440 now becomes available through Windows in the Change Resolution screen & games can now see and use that resolution. By default Windows Change Resolution uses the 60hz refresh rate, but clicking "advanced" link does show all refresh rates above 60hz and are available ("hide modes this monitor cannot display" box unchecked). By default, games will only use the 60hz refresh rate. One workaround is to enter the game and set that resolution (1440p) while the desktop is at 1080p, then minimize the game (via the Windows button, Ctrl+Alt+Del, or Ctrl+Enter) and change the desktop resolution to 2560x1440@100hz, then resume the game. In most instances, the game then runs at the new 100hz refresh rate. I know this is working because motion is smoother, lag is less noticeable, FPS go up to 100hz according to Fraps, and I confirmed every custom refresh rate via photos using Blur Buster's (super awesome!) frame skipping test. This is a hassle and is very time consuming. In some instances, games will continue to use 60hz refresh rate anyway, but I think those may be frame rate limited anyway.
2. Windows Change Resolution screen sees 108hz for 1920x1080p resolution, but still defaults to 60hz first. Games stuck at 60hz even with the above workaround for 1080p.
I can select the default 60hz resolution, then click advanced and select the 108hz refresh rate. It works and has no frame skipping, as confirmed via photos in the Vizio M651d-A2R thread. The problem is, using the above method of minimizing a game and changing the desktop resolution & re-entering the game does not work. The games will stay at 60hz. I'm assuming I could make 1920x1081 @60hz and @108hz resolutions and use the above method which works for 2560x1440@100hz and 2880x1620@88hz (which oddly is frame duplicating rather than skipping), but I am trying to figure out how to fix this so that Windows accepts the NVCP custom resolutions/refresh rates higher refresh rates as default. I really need to fix this, rather than add yet another work-around for 1080p resolutions.
- I uninstalled GeForce Experience (which I never used anyway) as it could cause issues, and have gone back and forth with several drivers, to no avail. I chose Clean Install as suggested each time.
- CRU utility is designed to raise refresh rates/timings, not for scaling/downsampling. ToastyX is pretty clear on that. Even so I tried using CRU for 1080p refresh rates, and the same issues are present for the CRU created resolutions as the NVCP resolutions.
- The PC is running Windows 8, so unsigned driver workarounds for using EDID overrides are not as easy as Windows 7, and must be applied/re-applied every time the system is booted/shutdown. Not much better imo than the current workaround I'm using.
- GPUs are 3-way SLI, not dedicated Physx, and obviously I'm using compatible drivers. I have tried disabling SLI, to no avail. Back in SLI mode currently.
- I have not used the CRU patch for NVIDIA pixel clock limit, as it doesn't seem to matter when using NVCP to create custom resolutions/timings. If I did, the patch would break HDCP (as I understand it), so using the PC for non-gaming media content would require reverting from the patch each time HDCP were needed.
- I have not tried 1600x900@120hz, nor 1280x720@120hz yet, but I assume they would have the same issues as all of the others. Either way, 720p isn't pleasing to the eye on 65" panels.
- This is a TV, so HDMI is the only reasonable option as the TV has no DisplayPort nor Dual Link DVI.
- I use NVCP's gobal V-Sync set to On (not adaptive) normally, but have tried disabling it as well. Only results in 100+ FPS with screen tearing because by default games run at 60hz. After the workaround, Fraps shows 100hz or 88hz with V-Sync on and no tearing.