Mystery CPU Diagnostic Light
I recently upgraded my 5,1 flashed 2009 Mac Pro to dual 6-core X5680s as well as 128 GB of RAM. Since this upgrade I’ve encountered a few issues that oddly don’t seem to be causing any problems following boot up.
Currently I’m dealing with a CPU diagnostic light that won’t go away no matter what I’ve tried. The strange thing is that when I power on the computer, the light shuts off and the computer proceeds to boot completely fine. I don’t see the OS throwing up any errors, it recognizes both CPUs are in place.
I’ve moved RAM cards around, pulled the heatsink and reapplied thermal paste, and attempted an SMC reset but so far nothing has worked. Any help in figuring this out will be greatly appreciated.
Edit: Both CPU LEDs are actually illuminated, I just didn’t notice the second one since it was obscured by the heatsink.