Multi Monitor Performance Hit Running SLI?

[steview77]

Hi

I've just had a new monitor, and rather than selling my old one I figured I could make use of it as an extra display. I don't want to run games over both displays.

My current system has 2x 970's running in SLI and what I'd like to know is, with 2 monitors running, when I run a game on my primary display, will there be a performance hit due to the second display being active?

I could just set it up and see for myself, but not really being up to speed to comparing these types of things I wouldn't know how to tell if there is a difference, short of seeing it, which I probably wouldn't.

Does anyone know for sure, exactly what difference it would make, if any? I'm guessing the second screen would still show but be unavailable for use, so use next to no resources?

Thanks

 

[HEXiT]

the hit will be minimal in most cases unless the game uses lots and lots of vram like skyrim (heavily modded) assuming both run at the same refresh rate.

also you cant really play games on 2 screens as the center point would be in the center where the screens join. some games will allow you to play the main game on 1 screen and have your player stats on the other but other than that your lookin at 3 screens for multi monitor gaming.


also be aware not all games will allow you to run a second screen a lot will actually disable the other while the game is running.
others will allow you to play a movie while you play your games. it just depends on how well the game is written and how good the driver support is.

i have 2 screens myself and while the other is handy to have its rarely on while i game.

 

[steview77]

That was quick, thank you! When I'm gaming on the main monitor, I won't need the second, so for all it matters it can be turned off/disabled so if games do this automatically, that's good.

Both monitors will run at 60hz, although sometimes the pc reports 59hz in some games, would this make a difference?

So are you basically saying, some games will turn the 2nd display off - therefore no performance hit at all? Some games will ignore the second monitor but so long as there is nothing crazy going on there, the GPU is clever enough not to waste resources on it?

 

[HEXiT]

yes pretty much... the gpu would still allocate some ram to it but only enough to display the backround image so about 50mb if that.
as for the refresh it wont matter. as the gpu would force both to 59-60. my samsung does the same but my lg is bang on 60 and ive not noticed any issues.

 

[steview77]

Brilliant, thanks very much for the info