I have a Mac Pro 4,1 with a Radeon 4870 which I understand I can support 2 monitors. I currently have a 24" Cinema display plugged into its display port. I'm going to be getting some retiring hardware coming my way and will score 1-2 more 24" Cinema displays. I'd like to line them up and create Megadesktop. First I went looking for DVI to Displayport adapters for Montior #2. Normally I'm pretty skilled at this Interwebs thing, but I couldn't find a single adapter. They seemed to go other way every time I got a search hit. Can this be done? I could upgrade my 4870 to a 5870 and get dual display ports available to me for that card, correct? Then, I went looking for a PCI-E video cards to plug into my open slots for monitor #3, or if I can't run two of these off the 4870, a pair of video cards with display port out. All I could find was the large, double cards that needed extra power, much like my 4870. Do any cards exist that take up a single slot? I thought I saw some Geforce GT120 refurbs -- anything newer? Am I barking up the wrong tree to run 1 or 2 additional 24" Cinema Displays?