Mac Pro 1.1 with 3.1 Logic Board

[kamimatze]

I was wondering if I can upgrade my Mac Pro 1.1 with a 3.1 Logic Board? I did a little research and the Boards look the same (Position of Ram, CPU and Screws), also the Power Supply should be the same wattage, so theoretically it should work.
Did anybody try such an upgrade or is it even possible?

 

[bax2003]

PSU connectors are different, and cables are not the same length. CPUs from 1.1/2.1 are for the same 771 socket but 3.1 board will not work with 1.1/2.1 CPUs and vise versa.....to many problems for today very cheap parts and Macs.

 

[MisterBiro]

Yes, it's possible, I did this with mine.

For it to work and look correct, you'll need to buy:

• Logic board
• CPU(s)
• Northbridge heatsink
• CPU heatsinks
• Front fan assembly
• RAM risers
• Memory cage
• CPU cover
• Wiring harness

You don't need a new PSU, but you'll need to modify the connectors so they plug together.

You may not need to buy a new wiring harness, as I believe you can modify the existing one, but I didn't attempt it.

You will need to remove the stand-offs used for the memory cage as they are in the wrong place for a 3,1.

Other than that, it's just like giant lego.

If you're not bothered about it looking right internally, I think you can get away without buying the CPU cover and front fan assembly.

I had to buy a new front panel, but I'm not sure if that's essential.

Also, make sure you get a decent 3,1 logic board. I went through 3 before I found one that didn't light up with errors on the diagnostics LEDs.

Edit: It was a lot cheaper than buying a 3,1.