Multi-Display with only One Card

[dv8silencer]

If I have one video card (say a high-end Nvidia GPU) that is connected to 2 monitors through DVI, how will this affect gaming?
For example, will the secondary display automatically be disabled when I start a game, or will I have to do this myself? Does it matter? I'm just wondering because maybe the gameplay will suffer if I'm running another monitor at the same time.

 

[myocardia]

You'll definitely get lower framerates, unless you just have the second monitor "mirror" the first. But what would be the point of having the same thing dispayed on two monitors, to begin with? Also, how much lower performance you'll get will be based on how fast the video card happens to be, and also what resolution(s) you're trying to run.

edit: No, the secondary display won't be automatically diabled. If you want it disabled, you'll have to do that yourself.

 

[panfist]

I have run a dual monitor setup through an ATI x1900XT and then nvidia 8800GT. I have not run any benchmarks, but I've never noticed a difference if I disable the second monitor or not. So there might be a difference, but it's small, and it's outweighed by the fact that I can display things on the second monitor like performance or temperature monitors, gamefaqs, IRC, etc.

 

[Lonyo]

Performance hit is minimal.
Games default to the single primary monitor (as decided in Windows display settings). Second monitor keeps displaying, and doesn't need to be disabled.

You can choose to have a game span across both monitors, but that's a choice and absolutely not necessary, so you can keep the second monitor enabled without any real hit on the primary/gaming screen.