MacPro (Mid 2010) Mountain Lion Compatibility Issues

I am unable to upgrade my MacPro to Mountain Lion. I spent a whole day trying, had Apple Support on the phone for over 2 hours. No Luck.

Here is what I tried and what I got:

- Bought Mountain Lion (OSX 10.8) from App Store and installed.

After installation, Mac won't boot. Keeps cycling on startup and shows messge "Your computer restarted because of a problem".... in several languages...

- Was able to go inte recovery mode: (Option-R)

- Did repair permissions, Disk repair, the works...

Nothnig changed

- Did PRAM reset. (Option-Command-P-R)

Nothing changed. Can't boot even in safe mode. (Shift)

OK, so my install package may be bad. Let's download again.

- Entered Recovery mode, did a new install. It downloaded a lot from the internet again.

Nothing really changed after the fresh install.

OK, maybe there is still something corrupt in my Recovery Partition. Let's REALLY start from scratch.

- Entered Recovery mode, Disk Utility, ERASED the whole HD, all partitions.

- Tried an Internet Recovery, using Option-Command-R. No luck. Apple Support told me my MacPro does not support it. OK, no problem.

- Went to another MAC, downloaded Mountain Lion for the third time. Opened the .app folder, found the bootable image, restored it into an external media using Disk Utility.

- Went back to my MacPro, booted from the external media with the fresh bootable ML. Went thru all the installation, all OK.

When it booted, I got back at where I was first thing in the morning. Boot sequence cycling over and over, "Your computer restarted because of a problem" message..

OK, we have a problem here. Maybe my Mac broke? By now I had also reinstalled everything on a different HD thinking it could be HD fault. Same problem.

So I then installed Lion back on the other HD. (this was a story in itself, since Apple does not have Lion for download anymore, so I needed help from those folks over in Scandinavia... its not warez if own the license...)

So now I have 2 HDs, one with Lion on it and the other with mountain lion on it.

Guess what? Lion boots just fine, ML does not. So that clears out any questions regarding my hardware.

And it all boils down to: Is Mountain Lion really compatible with the Mid 2010 MacPro?

Apple Support (very high level service by the way) exausted all its reccomendations and sent me to the store, but I decided to keep running Lion and wait for an eventual patch from Apple Developers. I assume I am not alone.

For the record, my MacPro has:

2x 2.66 Ghz 6-Core Intel Xeon and

16 GB 1333 Mhz DDR3 ECC RAM.

2 1TB HDs.

27" Led Cinema Display

All apple installed since new.

Any feedback from other MacPro ownners is appreciated.

Will post developments here.

Fabio Ribeiro