So I have a Mac Pro 1.1. As you guys know, it has the 32 bit EFI, but I bought it pretty heavily upgraded already. Specs Dual Quad 3.0ghz Xeons 32 gigs ram Ati 5770 Twin 500 gig HDs I bought this machine for around $1200 a few years ago, sold the cinema display that came with it, and so I had about $900 into it. I purchased a 128 gig SSD for 10.6.8 and win7, then put the twin 500 gigs in RAID array for media redundancy. I used it primarily for doing CAD modeling (solidworks), rendering and animation (Keyshot) in bootcamp; Layout and video editing in OSX. That was fine for a few years. I did freelance after my normal job, and I wound up making around 20 grand with this machine, but honestly it's still been rock solid and due to the SSD, usability is amazing. Feels brand new. Anyway, due to the size of Windows 7, I was running out of room in a 75 gig Bootcamp partition. I ordered a 240 gig SSD, and threw that into bay 2. I then downloaded 10.10 El Capitan onto a 32 gig USB stick, but it wouldn't install due to my 32 bit EFI. So I removed all my drives except the new SSD, and hooked up the Mac Pro to my 13 MBP using a Firewire 800 cable, and booted from the USB on the Macbook Pro. I selected the target SSD, install went smoothly. Due to the 32 bit efi, was not done yet. I needed to reinstall all the old drives, so I booted into Snow Leopoard. I downloaded the 32 bit/64 bit EFI hack from here: http://piker-alpha.github.io/macosxbootloader/ Installed that according to instructions here: 2006/2007 Mac Pro (1,1/2,1) and OS X El Capitan I then downloaded bootcamp, but that said it wasn't compatible, so I had to do some ******** with that too. I used the stock bootcamp tool and made the partition, but it wouldnt' boot from the USB stick no matter how many times I tried. So I had to burn a windows 7 DVD, boot from the win7 dvd, then select the partition.... thing is, it said it was the wrong format. The bootcamp installed MADE the partition, but windows 7 wouldn't like it. So then I booted into snow leopard again, deleted the partition, booted into elcapitan again, tried again, still no dice. So then I used the windows 7 cd to reformat ONE side of the partition, and the install worked! So the windows 7 installed, but I had no drivers. The bootcamp drivers from Apple would not run, it gave me an error message saying the computer was not 64 bit compatible. LIES!!!! So then I had to figure out how to get around that, using some ******** command line thing to run it in a different compatibility mode, I don't even remember. Thing is.... I didn't read the requirements on Fallout 4, and the 5770 doesn't meet them. So now I ordered an AMD 7970... should be here this Friday. Best card I can fit in this thing. Probably the last upgrade I'll do to this machine, but I'm hoping it sticks around until 2020 or so. So anyway. Now things are fine. Everything works. But what a pain in the ass. Back to another 4-5 years of not playing tech support again. Cheers!