Mac Pro Cpu upgrade Kernel Panic Issue

Apr 8, 2019
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Hi everyone- I didn't want to hijack another kernel panic thread but this one is an odd one after reading most of other issues on kernel panics online.

Currently have a mac pro 4,1->5,1 with dual 2.93ghz 6core cpu. I was having software issues upgrading from sierra since the machine was never updated for years. I got a new WD 1 TB HDD and installed a fresh sierra and upgraded all the way to Mojave. Bootrom confirmed was worked fine.

I decided to upgrade my cpu and swapped to the 3.46ghz de lidded duals last evening. Minus the red lights and rejigging the heat sink etc., i got to the apple logo screen but it never got to the desktop screen.

So, every keyboard option to get into safe mode or recovery ends up in a kernel panic. Even the NVRAM didn't help. Pressing Option key shows the HDD and when i select it, I get the kernel crash screen(see links to image below). I had the usb sierra installer and even tried that and same thing. I shifted the ram and made sure all is fine. My last resort was going back to the old cpus but thought I would check before i do. Right now, the only thing connected is my cinema display, my GPU 7970 amd, the ITB hdd with Mojave.

I see in the kernel panic text about MAC OSX not set. not sure why.

See attached images.

Kernel Panic

When booted using Verbose

Much thanks.


Cory Cooper

May 19, 2004
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Hello and welcome.

It sounds like there may have been some static damage, or other hardware issue(s) with the CPU board. The type of upgrade you performed is not officially supported or recommended by Apple or us, and it is way beyond our collective experience here.

The best recommendation I can give is to find a forum of folks that do hardware/firmware hacks on Macs.



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