Here's the rundown - that model's a decade old:

http://www.everymac.com/systems/apple/mac_pro/specs/mac-pro-quad-2.66-specs.html

http://lowendmac.com/2006/mac-pro-mid-2006/

Everymac says that the RAM can be maxed to 32GB. It needs firmware update to run an OS later than Lion. The unit's still viable for audio (256MB of video RAM is insufficient for editing, now). I wouldn't kick it out of bed. My late-2011 i7 Macbook Pro has this beat, but if I needed this, I'd pay no more than $300 for it (as I'd have to upgrade the video card and eventually the RAM). A guy I know is still running Pro Tools 6 (?) on his, and is still running Leopard on it, with 2GB of RAM. Dumbass.

 

This MacPro is still usable. I have the same mac as OP but with an upgraded video card and 28gb of ram. I'm running OSX 10.11 using a patch for the boot.efi and all my stuff works like a champ.

In addition you don't need to update the firmware to run OS later than lion.

 

All Mac Pros up to MacPro 3,1 (MA970/A), released January 8, 2008, use EFI32 mode and 32-bit kernel mode. You sure it works exactly like regular 64-bit Mac Pro? Are updates one-click with no messing around with config files and bootloaders?

 

WOW! Sweet door stop!

 

Isn't it obvious you have to patch the boot loader for a system that's not able to upgrade OS per factory standards. And yes it works as it should.

Seriously do some research before you start looking stupid bro.

 

Last edited: Jul 3, 2016