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flashed to 5.1

  1. SolidCake

    MP 1,1-5,1 Mac Pro 4,1 reboot loop after startup boot chime

    Hi all, My Mac Pro 4,1 (flashed to 5,1) enters a reboot loop when I start up the Mac. It keeps looping indefinitely until I manually turn it off by holding down the power button. When I turn it on again, or for the first time, it sometimes makes it past the boot screen and shuts down at the...
  2. At_Op45

    MP 1,1-5,1 4,1 cMP not booting after firmware/part upgrade

    Hi everyone, I hope this finds you well. I’m having some issues with my 4,1 early 2009 cMP. The issues came after I seemingly successfully flashed it to a 5,1 with the previously working configuration and shut it down to install new ram and CPUs. Previously working configuration: El Capitan...
  3. 9000EW

    Swapping one processor Mac pro 4.1 2009 tray to double processor

    HI There, I have a MP 4.1 2009 flashed to 5.1 and upgraded of a single processor and I have bought just the tray of another MP 4.1 but dual processor (it hasn't been flashed to 5.1). Currently I'm running Mojave and so far has been working great. I wonder what is the best way I can swap the...