MP 1,1-5,1 Tried Leopard 10.5 on Westmere?

[MrCheeto]

Related to a side project, Operation Norge.

Before I get too far into my build, I’d like to just do the easy thing and ask if anybody has done this already, or would be willing to give it a try.

Can you boot 10.5 Leopard onto a Westmere CPU?

If nobody else has or is willing to try, I will flash my 4,1 to 5,1, purchase a single CPU tray and a Westmere Hex Core CPU. I would start by using a modified kext (such as a hackintosh or else modify false to true etc), then try OCLP.

It’s quite an effort and I know that many on this board have completed 9/10 of the steps needed to answer if Leopard can boot and run on Westmere. Since it is a die-shrink of Nehalem, it’s been speculated that it should be no problem.

Certain hardware support I would sort out later, but here’s the starting point.

LightBulbFan has successfully booted Leopard on a genuine 5,1, so that much is not in question.

 

[h9826790]

I can't see why Westmere CPU cannot run Leopard.

The problem should be just Leopard itself not supporting 5,1. So, Leopard won't boot if it read the 5,1 board ID.

As long as you use OpenCore to spoof the 5,1 to 4,1. Leopard should able to run with Westmere CPU without any problem (of course, I assume all other hardware, such as GPU, are supported by Leopard natively).

 

[startergo]

Maybe simple -no_compat_check boot argument should do?

 

[macguru9999]

Without mods, the lowest I could go was mountain lion

 

[MrCheeto]

Without mods, the lowest I could go was mountain lion

That is strange. The 2010 shipped with Snow cat. Maybe it’s a GPU or expansion issue.

Maybe simple -no_compat_check boot argument should do?

I think just for booting, one only has to spoof their CPU ID. The rest of the Mac Pro 4,1 and 5,1 hardware appears identical to 10.5.

According to Amethyst1, Leopard checks for CPU ID.

According to LightBulbFan, actual Board ID checks started with Lion.

So it appears that one only needs to modify the kext within a boot image of Leopard OR spoof their ID. I bet if somebody has OCLP it would be very straight-forward.

 

[startergo]

Model checking may also be erased by editing OSInstall.mpkg with e.g. Flat Package Editor by making Distribution script to always return true in hwbeModelCheck function. Since updating the only file in the image and not corrupting other files can be difficult and may cause slow booting due to kernel cache date changes, it is recommended to script image rebuilding as shown below:

#!/bin/bash
# Original.dmg is original image, OSInstall.mpkg is patched package
mkdir RO
hdiutil mount Original.dmg -noverify -noautoopen -noautoopenrw -noautofsck -mountpoint RO
cp RO/.DS_Store DS_STORE
hdiutil detach RO -force
rm -rf RO
hdiutil convert Original.dmg -format UDRW -o ReadWrite.dmg
mkdir RW
xattr -c OSInstall.mpkg
hdiutil mount ReadWrite.dmg -noverify -noautoopen -noautoopenrw -noautofsck -mountpoint RW
cp OSInstall.mpkg RW/System/Installation/Packages/OSInstall.mpkg
killall Finder fseventsd
rm -rf RW/.fseventsd
cp DS_STORE RW/.DS_Store
hdiutil detach RW -force
rm -rf DS_STORE RW
hdiutil convert ReadWrite.dmg -format UDZO -o ReadOnly.dmg

Configuration

 

[MrCheeto]

That is to patch the installer, no?

AFAICS, it looks like this line refers to 10.6 installer.

 

[Amethyst1]

I can't see why Westmere CPU cannot run Leopard.

Leopard checks what CPU it’s running on. If it detects one it doesn’t “know” — and it doesn’t know Westmeres since these are newer than Leopard — it will kernel panic.

The problem should be just Leopard itself not supporting 5,1. So, Leopard won't boot if it read the 5,1 board ID.

Snow Leopard and older versions don’t care about the board ID.

Maybe simple -no_compat_check boot argument should do?

That's for Yosemite and newer versions.

That is to patch the installer, no?

Yes, it won’t get around the “Yikes, what CPU is this?!” problem. It only gets around the purely cosmetic “This version cannot be installed on this particular Mac model” issue.

 

[h9826790]

Snow Leopard and older versions don’t care about the board ID.

Thanks for the info. The lowest I've tested was the 10.6.4 ASD. Most likely because that's ASD, therefore, it check the board ID. Then, I wrongly assume Snow Leopard or even older OSX also check the board ID.