The Desire I have a 2009 Mac Pro. I want to drive, in OS X and Windows (Linux would be great as well), at least eight 15.4" retina displays at 2880x1800 that require display port input. Current Setup Currently I have two ATI Radeon HD 5770 cards and a NVIDIA GeForce GT 120 installed. I am able to drive 8 displays in OS X and Windows. The ATI Radeon HD 5770 cards currently appear to have no issues driving the 15.4" retina displays at 2880x1800 in Windows 8 and OS X 10.9. Currently the first 5770 card sits in slot 1, not blocking anything. The second 5770 card sits in the second slot blocking the third slot. The NVIDIA GeForce GT 120 card sits in the fourth slot. The Problem My problem is that I cannot physically install four ATI Radeon HD 5770 cards without modification due to the cooling fan. Three 5770s? My current plan is to hack the second part of the bracket off a third ATI Radeon HD 5770 card and draw power from the SATA ports for the PCIe 6 pin connector. This would potentially solve my physical and power issues, but only gets me 6 display ports total. Four 5770s? I was thinking about modifying a fourth 5770 card and the 5770 card in the second slot by removing the fan, removing the extra bracket, and replacing the heat sink with some water cooling that could be physically placed to not block the adjacent expansion ports. Then powering the extras with a second power supply. The end result would be four 5770 cards that can boot into OS X and drive 8 display ports at 2880x1800. But it seems like quite a bit of hassle. Alternative Solution I have an AMD FirePro W600 that works great in Windows in the Mac Pro. But I have not found an EFI upgrade for he card. I am hopeful that the support for the FirePro in the new Mac Pro would mean my W600 would have no driver issues once the EFI problem was resolved. I would love to use two cheaper VisionTek 7750 Eye 6 cards. After reading this thread I was disappointed to only find two nVidia cards with multiple display ports on newegg: HP GeForce GT 630, HP A7U59AT. And neither card can push 2880x1800. Found the PNY VCQK2000-PB Quadro K2000 at MicroCenter, does anyone know if it would work in OSX without modification? Picture of 15.4" Retina Monitor 2880x1800 Display Port input Thanks!