Do multiple monitors require more CPU usage?

[ziggo0]

Just wondering...I've ran 2 monitors for a while now and haven't seen any decrease in performance with the rig in my sig. Just threw this ancient Matrox MGA Millennium 4mb PCI card in and added a 3rd monitor. Will I see a reduction in performance with a 3rd?

[JigPu]

You should see just about the exact same performance hit adding the third monitor as you saw adding the second. The card (even as old as it is) shouldn't need the CPU for anything 2D so I highly doubt you'll notice.

JigPu

[drshivas]

Adding a PCI video card, in my experience, slows the system down, especially if there's a lot of I/O going on. The PCI bus has is slow as it is, and will have to do extra work to drive another video display. You'll get optimum performance w/ a dual head AGP / PCI-E card.