I chose the black screen as I dual boot into OSX Lion 10.8.5 or Yosemite 10.10.2. The black screen tells me instantly that I’m booting into Yosemite.Black is a white Apple on a black background and Grey is the traditional Apple boot screen: Either boot.efi file downloadable here.It would appear that Apple have asked for it to be taken down. We are sorry but the pre patched version of OSX Yosemite 10.10 is no longer available.I like a boot screen, so I purchased a proper Apple card (2nd hand) There are flashed PC cards out there, but they won’t display a boot screen. A graphics card better than a GT120, I used a Radeon HD 5770, original mac version with its appropriate power cable.A Mac Pro 1,1 or 2,1 Cheese grater desktop with OSX Lion 10.7.5 system drive.The clever bunnies out there in the Wild World Webby, have managed to fool a Ye Olde Mac Pro to run in 64 bit EFI. The main restriction for a 2006/7 Mac Pro is that it was designed to boot into a 32-bit environment, even though a lot of the internal hardware was 64-bit capable. The wait seems to have been worth it, as I now have my poor old machine running on OSX Yosemite 10.10.2 and Pro Tools 11.3.1 So I decided to wait a wee while until I found a more elegant solution. I’d read that some very clever folk had managed to persuade an old Mac Pro to run Mountain Lion and then Mavericks, and searching the Interwebs, I did indeed find a number of solutions that seemed to require entering a lot of commands in Terminal, creating boot partitions and generally patting your head and chewing gum at the same time. This is all jolly nice for my clients, but my own personal 2006 Mac Pro 1,1 with a Cinema display (purchased from a friend for a pittance) sits there languishing quite a few operating systems behind on OSX Lion 10.7.5 running Pro Tools 10.3.10 HD. All fully qualified, just the way I like it. They can afford the best, so I get to tinker with the latest Avid qualified hardware and software available: “iAshtray” Mac Pros, tank-like rack mounted Sonnet chassis, HDX or HD Native cards etc. Part of my day job is building Pro Tools rigs for high-end customers. You’re building what I refer to as a “Frankenmac”. If you end up with bricked Mac Pro, then it’s your own silly fault. First of all, all of the below are regarded as hacks.