After some intense trial and error combined with extensive forum browsing I managed to get OSX Leopard working on my trusty old desktop. I was quite satisfied with the results that I decided to summarise my installation experience so other people with similar hardware can travel a less challenging path.

My desktop configuration:
Intel Pentium 4 Prescott 2.8GHz HT Processor
Gigabyte 8IPE 1000 Pro 2 Motherboard
On board Intel Pro 100 VE Ethernet & AC97 Audio
2Gb Ram
ATI Radeon 2600 HD Pro 512Mb AGP
BenQ E2200HD Display

Previously I had an ATI Radeon 9600XT 256Mb AGP graphics card. However I could not get it to play nice with Quartz Extreme and Core Image. Best I achieved was 1024x768 resolution using the Natit driver. I probably could have done better and got a higher resolution with some obscure method but my 6th sense was saying forget about QE/CI given the lack of reports of previous success with this card. In my opinion running Leopard without proper QE/CI support defies the very purpose of installing it. Yeah I love my eye candy!

After frustratingly trying for couple of days to get QE/CI to get going I decided to upgrade my graphics card on the cheap and give Leopard one last try before throwing in the towel since that was the only show stopper. I have a fairly old desktop that is about 5 years old now that has AGP instead of PCIe. Given the limited option of cards that are available, I bought an ATI Radeon 2600 HD Pro AGP card. Happy to say it was a good choice! And now I get to play Doom 3 again with better graphics =)

Now what follows is the result of about 20 trial installations with various options and what eventually worked best for my hardware configuration. Starting as a total newbie to the process I can confidently say that I really didn’t know what I was doing at the start! Just getting OSX installer to get going let alone successfully boot post installation is an achievement for some. It really is luck of having compatible hardware.

I’ll spare you most of my agonies but I had to remove a secondary network adapter (Realtek chipset based) I had plugged in as it prevented OSX from booting all together in addition to having some issues installing to an IDE drive. Using a SATA drive atm. Verbose mode (-v) is your friend if you’re getting stuck!

Distribution: iPC OSx86 Leopard 10.5.6 [Intel AMD SSE2 SSE3] Final Release
Given the array of OSX distributions available, choice of this distro was somewhat of a random choice and maybe the keywords like “Intel AMD SSE2 SSE3 Final Release” made it sound comforting.

First install options
Kernel: 9.5.0 Voodoo Kernel
Video driver: Natit
Chipset drivers: Intel ICHx SATA Drivers
Audio: AC97 Audio
Ethernet drivers: Intel PRO 100/VE
Fixes & Patches: Seatbelt.kext 10.5.5

A word of advise with patches - only install on a need to basis. If you install a lot of unnecessary patches, chances are you’ll stuff it up. You can always install patches later once you have the bare bones working. Disabling non essential components/peripherals can only improve your chances as OSX is quite picky about all aspects of your hardware.

Post install what worked
With the above options I was able to get OSX to boot with 1050 resolution! I was quite impressed. However QE/CI was not supporting yet. Audio worked flawlessly out of the box. Networking was not so. It would say the cable is not connected and refuses to negotiate an IP address with the DHCP server. It will only establish a link if I unplug and replug the network cable. This can be quite annoying and sometimes even that method fails.

Post install fixes

Graphics
This thread was a god send
http://www.insanelymac.com/forum/index.php?showtopic=107526
Installed the relevant package, in my case (ATI Radeon HD 2600 Pro AGP, Device ID: 9587) reboot, and that’s it! 1080 resolution with full QE/CI support. Too easy.

Network adaptor

Original instructions from here.

Download and install these drivers. (you will have to sign up)

Reboot.

Open terminal and type following:

sudo -s
nano /Library/Preferences/SystemConfiguration/com.apple.Boot.plist

then add -f under the kernal flags section
(adding this flag also solved problems I had restarting & shutting down the PC)

then ctrl+x
then y
then exit terminal

Non essential fixes

Network printing
One word - CUPS! I have a Brother LH-5240 laser printer shared on my home Windows network. This is how I got OSX to print to it.

Install Brother MAC Drivers – brxubprt11c.dmg
Restart
Go to CUPS config page – http://localhost:631/
Add Printer
Type in printer info
Device: Windows Printer via SAMBA
Device URI: smb://machine name/printer name (i.e. smb://homepc1/Brother HL-5240)
Make: Brother
Printer Driver: Brother HL-5240 BR-Script3

I had some trouble doing this method initially as my Leopard user account did not have a password. Then I found this link which explained what I was experiencing and added a password to my user account which subsequently solved the problem.