G5 PCI Bandwidth - can handle 3 monitors?

I have a G5 Dual 2 GHz which has an ATI RADEON 9600 Pro 64MB AGP Video card. I am using both outputs of the card to run two monitors in dual monitor mode, so that the two monitors act as two independent displays

Now, I'd like to add a 3rd monitor that mirrors the display of Monitor #1. I am concerned about PCI bandwidth, since I use the computer primarily as a native digital audio workstation, with a MOTU 424 card and three MOTU 2408mkIII interfaces . I don't want to add unnecessary traffic on the PCI bus that would compromise my main work. I am under the impression that the possible solutions are:

1. Adding an older PCI graphics card (something like an ATI Rage Orion, which is a simple 16 MB PCI graphics card) on the PCI bus, hoping that the card would not need a lot of CPU power or PCI bus bandwidth to achieve my goal

OR

2. Take the output of the ATI RADEON 9600 card that feeds monitor #1 and run it through a DVI splitter (such as the DVI splitter made by Gefen)

http://www.gefen.com/kvm/product.jsp?prod_id=1403

which will split the DVI signal into two without using the computer at all, but costs $299 US.


So, will the increase PCI bus traffic that is added by the additional PCI video card compromise my audio system performance such that it should be avoided, or would it be so insignificant with the G5 that it is not worth worrying about? I have a spare ATI Rage Orion on the shelf here, solution #1 would be the low cost one, but I want to do whatever is best.

Thanks in advance for your response.