MP 1,1-5,1 cMP 4,1/5,1 stuck after back plate exchange

[DeppJones]

I recently had to change the back plate of my cMP 4,1 flashed to 5,1. Since I previously used x5680 CPUs and a PCIe drive I have to flash the back plate to 5,1. Here is where the problems start…

Every time I try to boot from a USB stick to install Mojave, the system stuck at:

AppleHDAEngineInput:erformFormatChange (<ptr>, <ptr>, 0)
IOConsoleUsers: gIOScreenLockState 3, hs 0, bs 0, now 0, sm 0x0

What‘s the problem? I have already removed all drives except the one for the Mojave installation.

 

[14dcutaneo]

If the new backplane board is not flashed to 5,1, it cannot take 5,1 CPU’s. Refer to this list as to which CPU’s you can boot with, and then flash to 5,1.

Mac Pro CPU Compatibility List

Bokkow and I have created a Mac Pro CPU compatibility list. The intent is to cover all relevant and compatible CPU upgrades for all Mac Pros. These are asked about over and over and over again, so I thought it would be nice to have it all in one place. Constructive criticism, corrections to...

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