Linux on the iMac - ATI Radeon 4670 vs 4850

English Hardware
1

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?

2

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

3

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.

4

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]([all variants] Installing Ubuntu Lucid Lynx 10.04 on an Apple iMac 11,1 27")
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).

5

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).

6

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

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

7

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

8

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.

9

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…

10

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).

11

That being the case (ie you never get the very first grub boot screen), then why quote a post as a ‘reference example’ that it ‘doesn’t work’ to prove a viewpoint, where they got further than you managed to get, and they did not not try the option that made the most sense and hence it does not prove it does not work?

I don’t deny its difficult, but the example URL is poor for making a point.

12

I had intended to say that I never got further than that with the LiveCD. I did invest a lot of time working on this with other methods such as the text-based installer (Ubuntu, etc.). I never had any success getting any distro up and running on this model iMac. It’s a shame because I would love to run Linux on it. After 8 months using OS X, I can say that I prefer Linux. (However, as I said, I reached the limit of the time I could justify investing – which was many tens of hours.)

13

Well, I am sorry to read you did not get it to work. I’m sorry to read you invested many tens of hours without success.

I did a search on our forum for user “MountainX” and “imac” and other than your recent posts on this thread, I could not find one thread where you asked our forum for help for an iMac with an ATI Radeon 4670 nor 4850. Its quite possible no one on this forum has an answer/solution for you, but one never knows unless one asks and you could have tried.

As a bare minimum you could have replied to the OP’s initial post on this thread to have the thread ‘bumped’ and this looked at again. During the 19-20-July time frame of the OP’s original post, I was away on business and not able to monitor the forum very much, and hence I missed the post, else I would have tried to set them in the correct direction.

Did you write a bug report on your difficulties in getting openSUSE-11.3 to install ?

… anyway … best of luck in your efforts.

14

Alternatively you can install Linux in VirtualBox under Snow Leopard, put it in fullscreen and nobody could tell Mac OS X is behind.

15

That’s an option. However, I’m concerned about having limited resources. One of my biggest complaints about OS X is that I always run out of memory and find myself staring at the spinning beachball while I’m trying to get work done. My iMac has 4 GB of RAM. My PC, which also has 4 GB of RAM and which runs Linux, seems to get a lot more mileage out of that 4 GB. My used swap space is almost always 0.

If I could have installed Linux on my iMac hardware, I expected that I would have gotten as much mileage out of the RAM as I do with Linux on my PC. But with VirtualBox, I suspect my memory limitations will be even more pronounced than they are under OS X alone. Your thoughts?

16

Your previous point about Linux not even booting is very valid. Is it correct that your iMac requires an EFI boot ROM instead of the traditional BIOS ?

Here is a page you could look at: HCL:Apple desktops - openSUSE
and also this page: User:Keichwa/Installation on iMac - openSUSE

17

That’s not really this issue. This is addressed with a tool called rEFIt that syncs the GPT and MBR partition tables and gives a nice UI to the EFI. In most cases rEFIt works fine for Mac owners who want to install Linux. However, on the iMac 11,1 (late 2009 27"), which I own, things don’t seem to work. The issues are complex (to me). They involve the video card, a bios-grub partition (sda3 typically) and a host of very small things that apparently conspire to make it nearly impossible to install Linux on that model iMac. Other model iMacs are not so problematic as far as I can tell (but I don’t own any other Mac).

18

Did you read the link I provided above? Specifically here: User:Keichwa/Installation on iMac - openSUSE
and I’ll quote part of the wiki:

Update : openSUSE 11.3 RC1 x86_64 on an Apple iMac 27" i7

I have tried the installation procedure in an Apple iMac 27" with i7, and performed the steps without a problem. After booting from the openSuSE DVD, the display resolution was not native, but it worked. Selecting 1920x1440 from the menu bar in the boot menu renders also a non-native resolution which is 2560x1440. The Apple Magic Mouse was not recognized, so the hardest part wast to perform all the installation without actually using a mouse. I didn’t tried to connect a regular USB mouse, but i think it would work fine. I didn’t had to say anything about GPT, as the bootloader was correclty configured. After finishing install, openSuSE asked to reboot, and simply hanged with a blank screen. I assume it stopped during the initialization of the graphics adapter.

Trying to boot from rEFIt gives the error “no bootable device – insert boot disk and press any key”. It was possible to boot openSuSE, using the DVD, selecting “boot from hard disk”, then “Failsafe – openSuSE”.

Tested configuration was: iMac 2.8GHz Quad-Core Intel Core i7 with Mac OS X 10.6, Apple magic mouse and wireless keyboard.

How many different types of iMac 27" are there ?

19

No need to quote it. I’m intimately familiar with all those details. I can tell you’re just getting up to speed on this and we aren’t communicating exactly in sync. I appreciate your interest, but we are beating a dead horse. I hit my limit – now I have OS X installed again.

The beautiful thing for me is that I installed a new SSD for Linux. Now I have OS X installed on that SSD instead and the already quiet iMac is dead silent. If the screen is blank you absolutely cannot tell if the thing is turned on or off. I love it. And boy do I wish I could run Linux on a piece of hardware that quiet and that beautifully engineered.

See here:
How to identify iMac (Mid 2007) and later models

The most problematic of all (for Linux installs) seems to be these:

5PE, 5PJ, CYB* iMac (27-inch, Late 2009)

20

No worries. I can understand the fatigue. Still, may I suggest next time, if there is a next time, you start consulting with others BEFORE you even come close to “hitting your fatigue”.

If you look you at my posts (and I can reference some if you are curious) you will probably see that OFTEN when I go to try something new, I often post here on our forum BEFORE I even start, laying out my plans, and noting the technical specifics of what I anticipate I will encounter. I would venture > 50% of the time, someone posts on my thread and advises me an easier / better way to do things.

In the majority of cases, we need to exchange a half-dozen to a dozen posts BEFORE they come up to the speed of my original research (ie we are 'out of synch" initially). BUT eventually they do come up to speed, and as a result a good % of the time, their input will result in a better approach for me. Which mostly means I never “hit my fatigue”.

That little bit of effort at the start, with a 2nd or 3rd opinion to bounce off my ideas BEFORE I start and at the beginning of my efforts, LONG BEFORE I “hit my fatigue” makes for me a MASSIVE difference in whether I succeed or fail.

One of the goals we have here with this user support forum is it should be a technical community to help not only when problems happen, but also BEFORE they happen. Indeed often before users purchase hardware, before they install the OS, before they install a driver. It does NOT have to be after everything falls apart, when one is forced to ask how to put it back together?

So my recommendation is to take advantage of it!

I don’t know what an “SSD for Linux” is. As noted by another user, you could try running Linux in a Virtual Session (albeit it WILL be slower).

Hmmm … it appears a number of different types. And some boot and some do not boot ? Not nice.

iMac (Mid 2010)
DB6, DNP* iMac (27-inch, Mid 2010)
DB5, DNR* iMac (27-inch, Mid 2010)
iMac (Late 2009)
5PE, 5PJ, CYB iMac (27-inch, Late 2009)
CYC, 5PM, 5RU iMac (27-inch, Late 2009)