Upgrading Mac OS

What is the latest Mac OS I can upgrade to, currently I have the following:
2008 Mac Pro with a 2x3 ghz dual core Intel xeon. 21 gb 667 ddr 2 fb dimm. I currently am running OS 10.7.5 Lion.

Without any modifications to your Mac Pro, and according to Mactracker, you can run OS X 10.11.6. (El Capitan)

Hold your hosses again Texan!


Mac Pros 1 and 2 use the 667MHz memory and can only run up to Lion OS X.7.5 so if you are at OS X.6.8 stay there. 2008 Mac Pro version 3.1 actually use 800MHz memory so methinks you have got the years mixed up. Your Avatar does say Mac Pro 1.1 and that is correct I would say.

With the 667mhz RAM...OP misidentified the Mac Pro being discussed. It's not a 2008 Mac Pro...it's really a 2007 Mac Pro.

If the Mac Pro being discussed is what's listed in the OP's profile. It's probably a Mac Pro 2,1.

- Nick

Maybe it would help if the OP just confirmed which exact Mac Pro model they have:
http://www.everymac.com/systems/apple/mac_pro/index-macpro.html

If Lion OS X.7.5 is it's max it can run, I'd agree with Harry and use 10.6.8 SL instead.






- Patrick
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Yeah, I looked at his profile but decided to go along with what he said in his post. If his Pro is as Nick stated, then he can only go to 10.7.5 and that's where he is now. Harry is trying to put me in the corral again! ;P

Opps, I missed the fact the OP said they're currently am running OS 10.7.5 Lion.

If it's working OK them no need to go back and use SL 10.6.8 unless they need Rosetta support.





- Patrick
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Thanks everyone for the help, to clarify, the system information says it is a Mac Pro that is a custom built to order quad core 3.0 (according to EveryMac.com) and it's serial number. I am sort of hoping that it could take a more up to date OS than Lion. If I try to install an upgrade what would happen?

cherokee2 said:

Thanks everyone for the help, to clarify, the system information says it is a Mac Pro that is a custom built to order quad core 3.0 (according to EveryMac.com) and it's serial number. I am sort of hoping that it could take a more up to date OS than Lion. If I try to install an upgrade what would happen?

Click to expand...

Sorry Cherokee. Missed the detail that your Mac Pro is a 2x3.0ghz dual-core CPU. This means it's even older (a Mac Pro 1,1...2006 model). Still "officially" limited to OS 10.7.5.

- Nick

You could go over to Mac Rumours as they do a fair bit of 'hackintoshing' early Mac Pros to run later operating systems. There are some risks involved, but many do it. I would strongly suggest if you are interested in this, to use El Capitan OS X.11 and leave it there. Some problems do occur if you upgrade the kext etc to handle a later operating system, and try to upgrade again later.

This will get you started on Pike's Updates etc:-


https://forums.macrumors.com/threads/2006-2007-mac-pro-1-1-2-1-and-os-x-el-capitan.1890435/

You could go over to Mac Rumours as they do a fair bit of 'hackintoshing' early Mac Pros …

Click to expand...

Also checkout http://www.xlr8yourmac.com that used to have a fair bit of info on modding most Macs under their various headings and threads.





- Patrick
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