Phew! I am away on business at the Moment and thought I would need to triple check when I got home to make sure I wasn't losing my mind
well it depends on if you're correct. I don't own a mac pro to test
As far as I am aware, it only works in Leopard.
So you have to boot a Mac OS X (10.5) Leopard partition then change the clocks and reboot into 10.6 ...
no.
wrong OS
wrong CPU
and that app broke the clock any way made the computer think time was moving faster in % to the OC %, buy a faster CPU if you need it.
List of cpu options here
https://forums.macrumors.com/threads/mac-pro-cpu-compatibility-list.1954766/
Thanks for the speedy reply. I am going to upgrade the CPU anyways, just wondering if there is any other way to overclock a mac pro.
If you know what clock chip it has you can use setFSB:
http://www13.plala.or.jp/setfsb/
If your clock chip is supported, you may be able to set it in Windows and Restart into the macOS, otherwise you'll need to use Grub's IC2 bus access, and boot the macOS with Grub.
I've done it before with Grub, on a few systems, but they were hackintoshes. I don't remember exactly how to do it, but if you clock chip is supported by setFSB, you glean the info needed from there, then use Grub's IC2 bus access to program you clock chip. Once you get it right, you create a Grub script that runs at boot time, then boot the macOS from the grub menu.
On a hackintosh you chianload Clover or whatever boot loader you want to use.
AFAIK, you can't set that in cMP, even in Windows. It may display the new number, but the actual speed won't change.
cMP may need pin grounded on the clock chip.
Do you know what PLL it is?I think so, no software method can achieve that at this moment.