I have been experiancing a screen blanking when playing some games (warzone2100 being the latest to expose this issue). This only happens on my main monitor (dvi connection) in my dual monitor setup (other is running off the vga connection).

I don't know what other information to give, but here are some system specs:

Driver: nvidia-drivers-260.19.12
GPU: GeForce 8400 GS 512M
Using twinview setup with minor modifications (generated by nvidia-settings)
Distro: Gentoo Linux

I really have no clue what is going on when the screen blanks. Any help would be appreciated.

ARe there any errors being spit into the /var/log/xorg.log?

No errors in Xorg.0.log. I am running the game on my 2nd monitor right now to see if I run into the same problem.

That is interesting. I am playing warzone2100 on my 2nd screen and my main monitor went black for a split second.