Linux on the iMac - ATI Radeon 4670 vs 4850

**zak89** · 19-Jul-2010, 14:16

I am considering purchasing an iMac 27-inch for my web development business; of course, linux-compatibility is a major issue for me. I know that Linux has been run successfully on various models of the iMac, including the 27 inch version, but of late it seems that the Linux graphic driver universe is going through a tough time. All that to say, I do want the large 27" screen of the iMac, so that's more or less my constraint (unless someone knows of other 27" all-in-ones - I certainly don't). I have two options from Apple - the Intel Core 2 Duo version, using an ATI Radeon HD 4670 for graphics, and the newer Intel Core i5/i7 version, with a Radeon 4850. Both of these cards are know to work under Linux, but I am trying to find what the status is of these chips on recent versions of the Linux kernel/Xorg stack/flgrx driver (as far as I know, the open source drivers do support the massive resolution of the 27" iMac).

I'd be surprised if many folks on these forums use the 27" iMac (but if you do, please report!), but I'm sure many people are using one of the above cards - any thoughts or experiences?

**My2CentsWorth** · 19-Jul-2010, 23:37

As someone that uses a Mac pro as my main computer and have installed several Linux distributions natively on my Mac Pro with rEFIt installed (rEFIt - An EFI Boot Menu and Toolkit). I removed every native install I did having to reformat the drives and return back to my External back-up drive state. I would suggest when you get whichever mac setup that works best for your needs, download the 30 day trial of Parallels Desktop 5 for Mac and see if that fits you needs. If it does then great buy it and load up as many Linux distro's on your Mac as you like to play hop back and forth between and play with them all. This way you won't have to worry about wireless drivers and video drivers, this is not the same old virtual machines we had years back that ran so slow no apps within you OS would function. Trust me try the 30 Day free trial and be a Linux Distro junkie like me.
Have Fun

**zak89** · 20-Jul-2010, 09:01

I have seriously thought about the VM option, and will certainly use that if there is any trouble running Linux natively; I'd rather not take this option, because the apps I'd be running (JVM instances and IDE's like Eclipse) would be heavy on their own, and I'd be taking a performance hit to some degree at least - of course, I'd try it before I decide.

By the way, to clarify my original question - I'm not a gamer and I don't really work my video card. I just want smooth desktop effects and full resolution.

**MountainX** · 17-Oct-2010, 13:33

Originally Posted by zak89

I am considering purchasing an iMac 27-inch for my web development business; of course, linux-compatibility is a major issue for me. I know that Linux has been run successfully on various models of the iMac, including the 27 inch version, but of late it seems that the Linux graphic driver universe is going through a tough time. All that to say, I do want the large 27" screen of the iMac, so that's more or less my constraint (unless someone knows of other 27" all-in-ones - I certainly don't). I have two options from Apple - the Intel Core 2 Duo version, using an ATI Radeon HD 4670 for graphics, and the newer Intel Core i5/i7 version, with a Radeon 4850. Both of these cards are know to work under Linux, but I am trying to find what the status is of these chips on recent versions of the Linux kernel/Xorg stack/flgrx driver (as far as I know, the open source drivers do support the massive resolution of the 27" iMac).

I'd be surprised if many folks on these forums use the 27" iMac (but if you do, please report!), but I'm sure many people are using one of the above cards - any thoughts or experiences?

I have the iMac 11,1. It is the 27" i5 model and I believe the video card is the 4850, but I can't check at the moment because I can't boot it up due to yet another failed attempt to install Linux. I've been trying to install various distros for a few months. No luck. It appears to be a video card issue. There are scattered reports of others having this problem.

I thought I finally found the solution when I found this post:
[all variants] Installing Ubuntu Lucid Lynx 10.04 on an Apple iMac 11,1 27" - Ubuntu Forums
Unfortunately, neither the original post nor the follow up comment worked for me. I tried repeatedly and carefully, so I know the lack of success was not due to me failing to follow the instructions. This particular iMac is different from others somehow (mine is completely 100% stock).

**oldcpu** · 17-Oct-2010, 13:52

I recommend you try openSUSE-11.3 using a liveCD. If the liveCD refuses to boot, then try again a second time and use the boot code "nomodest" (no quotes).

**oldcpu** · 17-Oct-2010, 13:59

Originally Posted by zak89

I have two options from Apple - the Intel Core 2 Duo version, using an ATI Radeon HD 4670 for graphics, and the newer Intel Core i5/i7 version, with a Radeon 4850.

If one types "man radeon" on a terminal in openSUSE one will see:

Code:

SUPPORTED HARDWARE
       The radeon driver supports PCI, AGP, and PCIE video cards based on the following ATI chips:
RV730       Radeon HD 4650/4670
RV770       Radeon HD 4850/4870

So clearly the graphic card is not an issue. Both are supported by the Radeon Graphic driver, and both are also supported by the propreitary Catalyst 10.9 graphic driver, which is noted in the documentation for that driver:

The ATI Catalyst™ Linux software suite is designed to support the following ATI Mobility™ products:
.........
ATI Mobility Radeon™ HD 4650
ATI Mobility Radeon™ HD 4850

The new 2.6.34 kernel implementation used by openSUSE-11.3 has KMS enabled, so it may be necessary to disable that (if one's boot attempt does not work) by the boot code "nomodeset". There is guidance here: SDB:Configuring graphics cards - openSUSE

**MountainX** · 17-Oct-2010, 14:04

Originally Posted by oldcpu

I recommend you try openSUSE-11.3 using a liveCD. If the liveCD refuses to boot, then try again a second time and use the boot code "nomodest" (no quotes).

Doesn't work:
openSUSE 11.3 on iMac i5 iwth ATI HD4850

**oldcpu** · 17-Oct-2010, 15:02

Originally Posted by MountainX

Doesn't work:
openSUSE 11.3 on iMac i5 iwth ATI HD4850

I'm not convinced that is the case.

That refers to the 'radeonhd' driver IF you read the error messages. Its the 'radeon' and not the 'radeonhd' that works with the graphics on that imac.

Also, that post only partly describes actions that should be tested. It does NOT follow all the recommendations in the openSUSE-11.3 release note which IMHO is the obvious thing to try.

What can I say? The user's efforts per that post were not complete.

If it were me, I would press F3 in the liveCD, and use the boot code 'nomodsest' and boot to a text mode. Login as user 'linux'. Then go to /etc/X11/xorg.conf.d/ directory. Type 'su' to get root permissions. Then edit /etc/X11/xorg.conf.d/50-device.conf and uncomment the 'radeon' driver.

And then save the change (which is saved in RAM), exit the editor and exit root permissions. And then type startx (to boot to the radeon and not the radeonhd driver).

The user did not try this. Honestly? From that post it suggests they were new to this and did not understand the full options available to them.

**MountainX** · 17-Oct-2010, 16:10

Originally Posted by oldcpu

I'm not convinced that is the case.

...

If it were me, I would press F3 in the liveCD, and use the boot code 'nomodsest' and boot to a text mode.

Well, unfortunately, if you were me, you wouldn't even get that far because on my Mac 11,1 the LiveCD will not even let me get to the point where I can edit boot options. I only get a black screen. That error has also been described in several forum posts. I think this specific iMac model is a tough one to install Linux on...

**MountainX** · 17-Oct-2010, 16:57

Actually, it looks like there may be a solution for the "installer black screen". I see a link here:
Can't boot from openSuSE 11 install DVD on new iMac

I probably won't try it. I just finished reinstalling Snow Leopard to my whole disk. I had reached my limit on this and I realized that even if I did get Linux installed on this Mac, I would still be facing many long hours getting the Magic Trackpad and Magic Mouse to work -- and much of their functionality would not be available at all. So I decided to punt and go back to OS X (which I definitely do not like as much as Linux).