Mac OSX 10.8 has broken my mac pro 2010

hk richard wrote:

Has anyone else had such a total failure?

Shouldn't there be a warning on this mac version of windows vista?

Never. On any of my 5 Macs. What warning should be given? There are millions and millions of users with ML not having your issues. Have you attempted to Troubleshoot? If so, what have you done to date?

Cheers

Pete

I have tried and failed to make Mountain Lion destroy any of my systems. I will keep trying though.

Your HD may simply have been defective. Sometimes they fail with advance warning, sometimes they don't. Replace it and restore your system from its backup. Whatever the problem is, Mountain Lion was not the cause.

hk richard wrote:

By process of elimination ML was the cause. System works fine with 10.6.8. I have perfectly good original HD (2010) and backup drives with time machine for this machine and household macbooks (wife and daughter). I download Lion, run install - and hey presto - Grey screen.

So we have tried start - option. No use but getting better. Can actually get to device select, I can insert original disk and select it - but it will not load. I have tried the recovery drive - that goes girectly to grey

We have tried control R and we can actually get the apple logo for a minute - before we go to grey

shift for safe mode - similar result

reset pram - no luck there

Given machine worked beautifully before this update - am pretty sure ML IS the cause. Of course begs the question - why did I upgrade?! I think to mirror the macbooks where ML works as the original software.

I believe I might not be alone with upgrade problems - but perhaps not quite so severe

Make an appointment with your local Genius Bar at your local Apple Store. Sounds like Hardware Issues. As I stated, this is not happening to 99.9% of usures, so you have a problem with your individual Mac by the sounds of it.

Good Luck

Pete

Why do you press Control R, it won't do anything. Try Command R, that's what you are looking for.

This is a stretch but the Mac Pro's Xeon CPU uses specific ECC RAM. Problems such as you describe might be attributable to memory that does not meet its required specifications, and OS X upgrades have been known for exposing hardware flaws for years. Not causing them, but revealing defective hardware - big difference.

Run Apple Hardware Test using your Pro's original Applications DVD. Its results can be considered conclusive only if the RAM fails its tests though. If it passes AHT, consider using Rember though its results may not be conclusive either.

Another suggestion is to download and install the Snow Leopard Combo update prior to attempting a reinstallation of Mountain Lion. ML is supposed to perform an exhaustive test for system compatibility but there is a possibility of missing something. Aftermarket replacement hardware, if that is a possibility in your Pro, is almost certain not to survive an OS upgrade.

hk richard wrote:

... Is it possible to launch the HD from another computer? If I boot in option while connected to one of the laptops?

I do not believe you can, but if it is possible, it would be accomplished by starting a MacBook in Target Disk Mode (hold the t key while starting it) and starting your Pro using Startup Manager (hold an Option key)... but you said your Option key isn't working.

Connect the two with a FireWire cable. I will try it and let you know if it works for me... it may take a couple of hours.

Edit: Please tell me you have not set a Firmware Password.

Typo's that are repeated across more than 1 post require questioning, thanks.

hk richard wrote:

- I have a firewire cable holding my cats' catflap up under the stairs where his ensuite toilet is - seriously!

⚠

Do not deny your cat access to his facilities yet. I will try it and let you know.

I do suspect a hardware problem will be the eventual diagnosis, and your GPU is as good a suspect as any.