I'm currently running 2 moniters, one on a GF3 AGP and another on an old Ati XclaimVR128 PCI as a palette moniter.
A buddy of mine is looking to set the same thing up, he has a MDD867, 10.2.6, and he's running a GF4MX (or a GF2MX? Doesn't really matter).
I'm seeing old ATI cards on eBay for under $10. I know his current card may be able to drive 2 moniters, but he doesn't want to split the VRam. And with old PCI cards so cheap these days... in many cases cheaper then a ADC-VGA adaptor!
What's the cheapest videocard that will run on a mac? It's just for palettes, so performance is not really an issue. Unless it somehow would slow down the rest of the computer, or other GF driven moniter. I've never heard of this happening outside of driver conflicts tho.
On a related note, I have installed the ATI drivers for my XclaimVR128. Did I need to under X? I'm not using any of the video stuff it used to be able to do, as it's just a palette moniter.