I notice input lag when running games with nvidia hardware comparing intel HD

Hello, after a few days learning a lot I decided to do a clean reinstall and try again.
I have a laptop with optimus (as I read on a forum, the worst idea in gaming hardware since the Sega 32X).
I installed ubuntu 13.04, bumblebee 3.2.1 and the nvidia drivers 325.15(from a non stable ppa).

I can run the games either with the intel harddare or the nvidia 740m. THe problem is that when I use the nvidia I notice an input lag, it is not a massive input lag, but it is quite obvious and annoying when playing games.

I have been using a very simple platform game “tomas was alone” to test the system. I noticed it was really hard to jump off the edge of cliffs. I have found myself anticipating the movements needed to play just to balance the lag, that is not right.

Is this normal? Do you experience it? is it a problem related to bumblebee?

try ftp://download.nvidia.com/XFree86/Linux-x86_64/325.15/README/randr14.html

Can reduce input lag by tweaking OGL_MaxFramesAllowed.

I notice something similar here on Windows and Linux and with two Laptops (Schenker XMG P505 and a Medion Erazer).

Playing CS:S with the integrated card resolves the input lag but that workaround doesn’t go well with games like DOOM or The Witcher 3 xD

It’s very noticable with DOOM where in the loading screen there is the Windows mouse cursor and it’s running smoothly. As soon as I press space and look around in the game, the lag is there.

Is this something that’s fixable or is it inevitable?
Maybe writing to the integrated framebuffer from the dedicated card just takes a fixed amount of time - idk.

What you wonder about is something else and something general about how graphics work on a computer.

The mouse pointer gets added by the GPU while the output is sent to the monitor. It’s not in the picture that’s in the graphics framebuffer. It’s not limited by the fps of a game’s graphics and not limited by VSync. Its position gets updated immediately when the mouse hardware messages new coordinates. It always has lowest possible latency.

If you currently use VSync for DOOM, what you could try is disable it and play with tearing. Get the fps as high as possible by tweaking the game’s settings and see how that feels. It still can’t ever be the same latency as the mouse pointer.