PC WEENIES: Tech Toons and Reviews | The Radeon 4870 Experiment

The Radeon 4870 Experiment

This weekend, I received the final ingredient I needed to test the PC-based Radeon 4870 card in my Mac Pro: two molex power connectors.

My hope was to chronicle the experience of flashing the card to work inside a Mac. Unfortunately, I never made it that far.

The steps to flash a PC card to a Mac are documented online. In the process of my research, the basic steps are as follows:

back up the existing BIOS of the card on the Windows side using WinFlash or GPU-Z
Save the BIOS information into a data file that can be accessed on the Mac side
Use the Zeus application on the Mac to flash the card

Installation of the card itself wasn’t too terribly difficult. The most challenging aspect of the install was plugging in the two molex power cables into the motherboard of the Mac Pro. It requires nimble fingers, mild profanity and persistence.

Next, I moved the existing Radeon 2600 card to Slot 4 and inserted the Radeon 4870 into Slot 1.

With the display connected to the Radeon 2600, I was now ready to install Windows.

There was no way around installing Windows; it’s required to run GPU-Z 0.5.5, an app which basically serves as a video card BIOS reader / extractor. After a few hiccups in the Windows installation process (it’s a mild PITA to clean install from a Windows 7 upgrade disc), I was able to finally install GPU-Z. Unfortunately, GPU-Z was unable to extract the BIOS information from the card. That was the first roadblock.

Windows 7 was able to recognize the presence of the Radeon 4870, so for giggles, I decided to connect the display directly to the 4870. I powered down the Mac and made the appropriate connections before rebooting back into Windows. Another road block: the Radeon 4870 was not generating any video signals to the display.

That’s where I left it. If the card wasn’t working within Windows, I’d never be able to flash it for the Mac.

Total time spent in my testing (including the Windows 7 install): 6 hours.

Conclusion: It was an educational experience, for sure, but after all the time I invested in attempting to get the card ready for flashing, I’m left with the notion that it would have been far easier to purchase a pre-Flashed Mac version of the card (on eBay) or a Mac edition Radeon.

I’m open to hear any thoughts or feedback you might have on this.

-Krishna

Krishna November 1, 2011 ATI Radeon 4870, Mac video cards

These beautiful and intelligent people wrote

EricReply
November 1, 2011 at 10:56 am
The problem with a flashed BIOS on the card is that when you upgrade to OS X 10.8 Puddy Tat, it’s probably not going to work. But who knows? Good luck!
- Bansaku Reply
  November 2, 2011 at 6:06 pm
  Actually it will. I have used a flash card from 10.5.X all the way up to 10.7.2 with zero issues. As long as Apple continues 4800 support, the card WILL work.
qkaReply
November 1, 2011 at 11:19 am
It’s not profanity, it’s mechanical incantations.
DabbithReply
November 1, 2011 at 11:24 am
While I’m not very familiar with Mac’s, on a PC the PCIe power connectors on the motherboard are for Power In (from the power supply to the motherboard), not for power out (from the motherboard to the video card). You most likely need 2 MOLEX 4-Pin to PCI-Express Cables. If you don’t have any MOLEX connectors, you could get a dedicated GPU power supply like a Visiontek 900222.
JamesReply
November 1, 2011 at 11:26 am
Installing Win7 upgrade requires clean installing and not activating then install a second time and it can upgrade itself then the activation will work.

Got a PC to test the replacement card on? Not sure if booting into Win7 on the Mac will allow the video to work like it will in PC. i.e. the reason you have to flash the video card is because of the diffent Mac EFI firmware and architecture difference. You should try the card in a PC and it should work until you flash it. Then you move the card to the Mac Pro. Maybe you have a friend with a PC that could come over and loan his box temporarily.
- KrishnaReply
  November 1, 2011 at 11:30 am
  Great suggestion, James. I’m planning to try the card in a dedicated PC to confirm whether its truly working or not.
MoReply
November 1, 2011 at 11:28 am
You do not need to install Windows 7 to flash the card. I have been using a 4870 that I flashed myself for two years, I just made a DOS boot CD, booted from it and flashed the card with command line utility ATIFlash.exe.
- KrishnaReply
  November 1, 2011 at 11:30 am
  Thanks, Mo. I wish I knew this beforehand. Appreciate your tip!
MoReply
November 1, 2011 at 11:39 am
The Mac Pro MB does not play nice with some 4870 cards and will refuse to show video on them. The Mac Pro motherboard only really likes cards that are based off of the reference ATI design. Some third party cards that work perfectly fine on a PC but that differ from the reference design will not work on a Mac Pro
- BansakuReply
  November 2, 2011 at 6:08 pm
  To get around this issue, manually add the device ID to the appropriate plist inside the ATI4800Controller.kext and ATIRadeonX3000.kext and you are good to go.
robboxReply
November 1, 2011 at 12:58 pm
depending on your MacPro version, I’d recommend the 6870. Installation is a LOT simpler, visit MacRumours for full instructions.
GiridharReply
November 1, 2011 at 10:09 pm
You quit when the fun starts! hardware tinkerin has long times, specially when you need to reinstall an OS. Borow a friends win7 machine, or better yet get one! =D