ALT+TAB causing screen to black, SOLVED

If you have black screen after ALT+TAB or going to a second screen app then coming back to your main screen, then it might be fixed by these methods.
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Dwm] "OverlayMinFPS"=dword:00000000
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer Create a dword value called AltTabSettings and set it to 0.
G-Sync reset in NVidia CTL PNL
Check Monitor refresh rate to be same a PC settings, and in NVidia
CTL PNL Adaptive Sync on Monitor, or G-Sync Game Mode, OFF
Optimizations for windowed games, OFF
Use NVidia Color Settings with PC Native rate
HAGS, OFF
Hardware Acceleration Mode, OFF on PC, Discord, Steam, Race Labs, and Google
Updated Windows 24H2 version 9-30-25 and latest NVidia GPU drivers.
The issue is most likely caused by some interaction between Windows OLDER version build of 24H2 and OLDER GPU drivers.

• In Game set to Borderless, buffer 1 frame in advance.,
• Then select "just" AMS2 for Optimized for Windowed games.
• You WILL NEED the 2025-09 Cumulative Update Preview for Windows 11 Version 24H2 for x64 based systems, and it NEEDS to be this version, (KB5065789) (26100.6725)

This issue drove me nuts TBH, and I actually had all those settings above already done previously, but it wasn't until I did the NEWEST 24H2 update and the latest NVidia GPU driver updates (581.29) did it correct itself. Note, your GPU driver may be different depending on the model you have.

Now I can use Borderless mode in-game, and get the same performance as full screen, and be able to switch between monitors and app's without any black screens or game loss.

Just for reference I'm using an Intel i7-13700K / 32GB DDR5 ram, W11, RTX 4070Ti / 12GB VRAM
144 Hz refresh rate on gaming monitor, and 60Hz refresh rate on second second monitor.
Gaming Monitor is set for G-Sync+VSync+Ultra low Latency, FPS capped at 144Hz.
In Game is Borderless, NO VSync in game, render 1 frame ahead.

I typically get 138FPS with 9 cars on track, and 4.6ms latency delay.

Hope this may help others who may have run across this now or later.
Cheers