08-16-2011, 03:57 PM

Well, in case you are one of the unlucky people whose Geforce 8800 GT broke down in an early 2008 Mac Pro (Mac Pro 3,1), here is a nice solution which does not require you giving huge amounts of money to Apple for - well, nothing, basically
In case you did a little research, you will soon find out that Apple's graphic cards are - except for their EFI Bios - basically identical to "normal" PC ones. So the interesting question remaining is whether they are or are not usable within a Mac Pro. And the answer is:

You can make an PC ATI Radeon HD 5450 working in a Mac Pro 3,1 WITHOUT ANY EFI-FLASHING and WITHOUT ANY SPECIAL DRIVERS. This tutorial SHOULD WORK WITH ANY Radeon HD 5xxx (though this isn't tested)

The basic idea is taken from ATI Radeon HD 5450 Working On Snow Leopard - InsanelyMac Forum so - thanks :-)

As you may or may not know, current graphics card drivers are seldomly for one specific card only, but instead for a whole series. So the thinking is - if Apple provides drivers for the Radeon HD 5770 (indluded in Snow Leopard), these drivers should work with each card of the series - in this case, all Radeon HD 5xxx.
The only problem is that Snow Leopard will take any non-5770 as "not compatible", and will not provide any graphics with these cards at all. But we may - our purpose here - tell OSX to use the drivers for the 5770 for all 5xxx models, something which may be achieved with a simple alias. And the really nice thing is that such an alias is - when it comes to OSX - not more than a simple text file (i.e. a *.plist file).
So all we basically do is telling OSX to use drivers it already has for different graphics cards. Thus we do not need to manipulate the system at all!

The steps needed to be done:

1. * visit the link above to the insanelymac-forum and extract the all-in-one zip file
   * copy the ATI5000Injector.kext "file" (this is not more than a folder with just one file - the above mentioned plist file) to /System/Library/Extensions (/s/l/e)

And - you are done! The one and only drawback is that the screen remains black until the graphic environment is loaded, i.e. until you log on the system. Once you are there, you have the full control as if any normal Mac Pro card was installed (rotating screens, changing resolution, etc.).

Even with a "cheap" HD 5450 you can run two screens with resolutions of 2560x1600 and 1600x1200 at a time without any loss in everyday performance - for a mere $50.

If you have a Geforce 8800GT and cannot enter the graphics environment but still can see the startup screen, try the single-user mode (instructions for how to get there, how to mount an external drive (to copy the files) and how to copy these are all over the net).

This was thoroughly tested on a MacPro 3,1 (early 2008) with a Sapphire Radeon HD 5450 (dual-DVI version) running Snow Leopard.

So - hope you will add your experiences with this any time soon - I'm especially curious if this instructions work for other Radeon HD 5xxx (as they should) or different Mac Pros (as they should as well).

03-28-2012, 09:17 AM

Hi, I've given this a try on my Mac Pro 3,1 running Lion 10.7.3
When I drop it in the S/L/E though it tells me an error occured installing it. The card therefor is not working.

I used the exact same card:
Sapphire Radeon HD 5450.

Does it still work for you?

Thx in advance!

04-07-2012, 07:25 AM

Tried on Mac Pro 1,1 w. Lion.

Does not work, same issue as above. If someone made it work would love to hear about it.

04-07-2012, 06:57 PM

Well fellas flashing PC cards is not for the faint hearted and often ends in disaster.

05-22-2012, 01:35 PM

A very big thank u for everbody trying and showing me the way....!

Pc card amd radeon HD 5450 working smooth so far on my mac.
After boot failures i decided to take a chance with this pc card ( 31 Euro )...
No time for ordering .. i needed it instant...
out of the box ...into the mac ...startup in safe mode...(i still have original Nvidia 7300 GT in the slot ...somehow only working with safemode at 800x600 vga)...downloaded a ATI5000Injector.kext.zip (ATI5000Injector.kext.zip)
...and dragged it into the folder where all the .kexts are located ...
..i did got some failure comment after that ...
update software just in case and restart..plugged in my second dvimonitor in the new radeon 5450....mac rebooted twice and ...it works!
No faillure comments cards gets detected as a ..Chipset Model: ATI Radeon HD 5000 ..
on a Mac Pro 10.6.8 snow leopard 2x2,66 dual core intel xeon mac pro 1,1

peace out