12 Core Mac Pro 4,1 Issue

I have recently acquired a MAc Pro 4,1 12-Core machine. It boots up and i can get into the installer for 10.11. But, it locks up after it loads at the apple screen. I once got it to load into the desktop, but it froze there as well. I've tried 3 different hard drives and 2 good sets of ram. I've also tried a few different installers. Am i looking at a larger hardware problem like the board or processors?

Sorry, im new to Mac, but have a pretty good idea bout PCs. Thanks for the help.

Since you tried differenrt RAM...and different HD's (with seperate installs of the OS)...I would next look at the video card.

Since this Mac Pro is new to you. What claims did the seller make as to it's operation? If you bought it broke...it very well could have something very serious wrong with it...which is why it was sold.

- Nick

Thanks. Swapped the video card, same issues. I got the machine from surplus, so no claims as to it's functionality. Just trying to make it work. It was so promising, too. But i fear a fairly serious issue is the cause. Im currently looking for apple diagnostic tools to help figure out the issue.

Amoed77 said:

Im currently looking for apple diagnostic tools to help figure out the issue.

Click to expand...

There really isn't that much available for us DIY troubleshooters. About the best you can do is swap known good parts for possible bad parts.

One of the big issues with this computer is the locking up or freezing. Can't do much software based troubleshooting when this happens.

One other thing to try is booting into Safe Mode:

https://support.apple.com/en-us/HT201262

- Nick

If this MP is a 4,1 then it is a 2009 model. If it is running 12 cores then the firmware has been flashed to allow it to act as a 5,1 2010 model. The stock 2009 4,1 did not allow for more than 4 core processors but since the architecture is the same as the 2010-2012 models it can have its firmware modified to allow it to operate as a newer model.

While flashing the firmware can work well, it does open a whole host of other potential issues. You do not say if this MP was running an older version of OS X with no issues and if so what version was it?

There is a bunch of information on the MacRumors forum about mods for the classic MP. I do not profess to be an expert - just a lucky modifier who has a lot more Windows experience. I suggest you check out this link: http://forums.macrumors.com/forums/mac-pro.1/

Lisa

I stand corrected, this is a 5,1. just looked up the SN.

Not sure if this will help but the link below is a pdf of the technician guide for your mac pro.

http://tim.id.au/laptops/apple/macpro/macpro_mid2010.pdf

Lisa