Emulating a PowerPC under Linux on x86 is very simple. One of the programs that can do it under Linux x86 is SheepShaver. The same person that wrote SheepShaver for x86 also helped write BasiliskII/JIT which is a special version of BasiliskII that can perform instructions much faster than BasiliskII itself. But we wont go into installing that as this is a guide to installing SheepShaver x86. The requirements for SheepShaver x86 are: Linux(installed), Mac OS(from 7.5.3 to 8.6), a PowerPC ROM(included on the Mac OS 8.6 CD), and, possibly, Wine. You can get a ROM from another computer, and so far, the only ones known to work are from a PCI-based PowerMac, models 7500, 8500, and 8600. The ROM I used is from a Mac OS 8.6 CD. It works perfectly.
Here is where the Mac OS 7.5.5 update is located: Download
Part 1: Downloading and Compiling
2) In your terminal window, type cvs -d :pserver:firstname.lastname@example.org:/cvs login and press Enter. It will ask for the CVS password, type 'anoncvs', no quotes.
3) Now type cvs -d :pserver:email@example.com:/cvs checkout BasiliskII and press Enter. It will download a bunch of files, and when it completes, type cvs -d :pserver:firstname.lastname@example.org:/cvs checkout SheepShaver and press Enter. More files will be downloaded...
4) Ignore the BasiliskII directory and type cd SheepShaver. Once in the SheepShaver directory, type make links.
5) After thats done, type cd src/Unix, and then type ./autogen.sh. Ignore the warnings about AM_GTK, as it compiled fine for me with those warnings. After the script finishes, it will tell you to run make, so, type make. Once that finishes, you can either type ./SheepShaver or, if you want it available to all users, type su root, type your password, and then doing make install. After that finishes, exit root, as you no dont have to be root to use SheepShaver.
Note: you might have problems running ./autogen.sh or make. If this is the case, install ALL development packages for your distribution. If you use SuSE, this can be done via YaST. Then try it again.
Part 2: Configuring SheepShaver
2) Under the Graphics/Sound tab, set the Window Refresh Rate to 5Hz to take the load off of the virtual machine. It will run slow enough. For Enabled Video Modes, I believe that Fullscreen modes arent implemented yet, so either choose Window 640x480 or Window 800x600. For the bottom audio settings, you can either choose to disable or leave it enabled, and set your output and mixer devices, most commonly /dev/dsp for the output device and /dev/mixer for the mixer.
3) Under Mouse/Keyboard, the defaults usually work, but if you are outside the U.S., you *may* have to play with the Keycode Translation File option. The Mouse Wheel Function and Lines To Scroll options are pretty obvious, usually the default is fine.
4) For Serial/Network, the default Modem Port and Printer Port options are fine, and for Ethernet Interface, leave it blank, as the SheepNet driver, which provides Ethernet for the virtual machine, is broken. I couldnt compile it, but if you're good with C/C++, give it a fix.
5) The Memory/Misc tab is where you set how much RAM you want the virtual machine to have, where to set its ROM file path, and the Ignore Illegal Memory Accesses function. I would set the RAM size to either 16/32/64/128/256MB, depending on the amount of RAM you have. I have 1280MB and I set mine to 256. Set the ROM File to where you have your PowerPC ROM stored, such as /home/joe/SheepShaver.rom in my case. I would leave the Ignore Illegal Memory Accesses option enabled, all it does is lets programs access RAM that doesnt exist, it shouldnt cause much trouble, but I like to leave it on. Feel free to change it.
6) The last tab, JIT Compiler, has one option. Leave it enabled, put simply, it sort of "recompiles" to make it run alot faster.
7) After you set things up the way you like it, click Start. Give the emulator 30 minutes to get going. Subsequent starts wont take as long. Note that SheepShaver isnt fast at all, not like BasiliskII compared to an older Mac.
8) Have fun emulating the PowerPC.