Restrictions on Apple hardware

I was recently looking for a link I thought I’d bookmarked on how to install recent versions of Mac OS X on EoL Apple hardware, specifically the Mac Pro. I was unsuccessful in finding the link I was looking for but I did find that  you can re-flash a MacPro1,1 with a MacPro2,1 EFI firmware, main benefit being microcode updates. Turns out the hardware in the first & second generation Mac Pro is identical bar the model of CPU available. There’s also modified images to bring the MacPro4,1 to 5,1 which seems to provide much more benefit than the previously mentioned modification.

This got me thinking about some of the issues I’d experienced with older apple hardware and the work arounds, it has been a while since I’ve posted something here so I wrote this post.

On the old world SCSI Macs (pre biege G3?) the drive vendor on the disk firmware with be identified as Apple which the Drive Setup utility (predecessor of Disk Utility) would look for, if it was not found, you would not be able to format your drive as HFS and hence be unable to install Mac OS. Work around was either finding another platform to format the disk or modify a copy of Drive Setup utility with ResEdit & add the drive to the necessary table.

The first of blue & white PowerMac G3 systems logic board shipped with a buggy CMD IDE controller which would corrupt data when doing DMA transfer, Apple shipped the disks in these systems with the firmware tied to PIO mode which was lots of fun when you came to replace the disk with a newer/bigger/faster one. To complete the replacement successfully, the new disk with need to be connected to a PC first & using the firmware utility provided by the vendor, make the same change of restricting the disks operation mode to PIO, otherwise it would not be possible to rely on the disk as data would be corrupted as you began writing to it, there was a recall for the motherboard If you were aware of the issue at the time.

The Mid/Late 2007 MacBook Pro (per advisory?) has the SATA port on the ICH8-M south bridge locked to SATA I even though it is capable of SATA II.

Most systems with user replaceable RAM are capable of taking more than official specification documents list. MacTracker – an application which lists specs & information about Apple hardware provides advertised & actual maximum memory capabilities of system. Not so much a software based restriction but a documentation one.