Windowed mode having permanent V-Sync effect?

[Haswellx86]

I remember that the reason I quit CSGO was because I didn't get smooth 60 fps gameplay. I do get 60 fps or above if run CSGO in proper fullscreen mode, so that it renders more directly on the screen which does improve performance, but the problem I was facing, and still, I am facing is that most, if not all, of the games that run in proper fullscreen mode (not fullscreen windowed) have issues running in lower resolutions than my monitor's resolution. There is always this black screen that comes if something goes wrong (but the system is running fine, I just can't see anything). Most of the times they can't run in stretched resolution (even if I set it to) and other times they will even fail to at least run with black bars. One day with talking with a Microsoft customer service, I did get stretched resolution working, which is what I wanted for CSGO as it not only gives me more fps, but also stretching the screen means it's easier to hit targets. But the problem that it wouldn't work if CSGO was running in proper fullscreen mode, rather it worked on fullscreen windowed mode. I did keep playing CSGO after that until I realized why I was feeling a weird input lag. After some experimentation, I found that having proper fullscreen with black bars does properly show the tearing artifacts that I can see with V-Sync off, but with full screen windowed and stretched, it was weird that I could see some hitching on the screen, but it was significantly less than what I had with proper fullscreen, and visibly no tearing! Even when V-Sync was off, obviously. Exactly same thing applies when I play Doom 3, where if I play in fullscreen, I can say for sure that V-Sync is off, and I play in windowed, it smooths out quite a bit. If you render a game over the layer of Windows, does Windows something use V-Sync or something like that? Because I really want to turn it off please.

[Levent]

Windowed mode will default to desktop refresh rate (which is also enforced as maximum frame limit and synced). AFAIK, you cant disable vsync unless you run your game in fullscreen/exclusive fullscreen.

[Haswellx86]

@LeventIsn't there any way to disable that? Probably not, I guess. But one another way you can help me is to see how I can get stretched resolution in fullscreen mode. It looks like it doesn't have official support from the GPU or the drivers to stretch the resolution, that is why it needs fullscreen windowed to get help of Windows or something? I will try updating my GPU drivers...