Drop in performance. Linux (intel/nvidia).

[Ramsay]

Very often, at any time, a reduction in the level of FPS during the game. Only helps to restart!

[bob]

Have you tried any of the other drivers available?

[Ramsay]

Current nvidia driver: 340.17. But this problem is very old. I tried drvers 33*, 32*.
My system: Gentoo ~x86_64, intel i5-3450, nvidia gtx-550ti

[bob]

You know, I actually had a similar problem when I had a gtx 550 in Ubuntu- randomly would go down to 9 FPS and l4d2 would be using up 90% of the cpu or something. I could run the game in the smallest resolution in windowed mode, though, with one of the drivers, can't remember which. Didn't have same problem in Windows, and with a different gpu I don't have any trouble. It might just be the drivers for the 550, I guess. Try changing your resolution and display mode to see if there's something that works.