My 5,1 MacPro (upgraded from 4,1) will not reboot. It starts, shuts down, enters sleep, and leaves sleep without any problems. It can't restart from neither Max OSX Yosemite, Windows 8.1 nor Windows 10. When I choose restart, the OS shuts down, GPU fan spins down, and the front LED goes dark. But the computer is not entirely shut down and system fans are idling. I have to manually press and hold the power button, wait for a slight click sound, then press the button again to start the boot up.
I've got
Xeon W3690
16GB OWC 1333MHz DDR3-RAM
250GB Samsung 850 EVO
500GB Samsung 850 EVO
2TB WD Green
Custom MacEFI AMD 7970
Custom MacEFI AMD 7950 in Crossfire (With Spliced 12V cable from power supply)
The computer has had this issue ever since I bought it (used) about a year ago.
I've tried the following:
Reset SMC & PRAM
Use original CPU with,
original 3GB RAM (3xGB),
original 1GB RAM (tried in slot 1 2 and 3, only slot 1 boots)
original GeForce Quadro FX 4800
original 1TB HDD (removed all other disks + optical drive)
Replace motherboard battery
Running Apple Hardware Test (no errors given)
(I had this issue before splicing the 12V cables on my PSU)
I'm suspecting Motherboard or PSU. What do you think?
I've got
Xeon W3690
16GB OWC 1333MHz DDR3-RAM
250GB Samsung 850 EVO
500GB Samsung 850 EVO
2TB WD Green
Custom MacEFI AMD 7970
Custom MacEFI AMD 7950 in Crossfire (With Spliced 12V cable from power supply)
The computer has had this issue ever since I bought it (used) about a year ago.
I've tried the following:
Reset SMC & PRAM
Use original CPU with,
original 3GB RAM (3xGB),
original 1GB RAM (tried in slot 1 2 and 3, only slot 1 boots)
original GeForce Quadro FX 4800
original 1TB HDD (removed all other disks + optical drive)
Replace motherboard battery
Running Apple Hardware Test (no errors given)
(I had this issue before splicing the 12V cables on my PSU)
I'm suspecting Motherboard or PSU. What do you think?
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