Updating a working hackintosh pc is risk task. Make sure you have good backup. You can use timemachine or superduper.
Ok, I updated 10.5.5 to 10.5.8. Here is the step by step:
1) install disabler.kext and dsmos.kext
2) reboot
3) I assume you have created full backup before, so now take the risk. Download 10.5.8 combo update from apple website.
4) After installation finished, it will reboot. If it take long, then it may your reboot function doesn’t work. Wait until 30 minutes or force to shutdown with pressing power button for a few seconds.
5) Boot as usual, leopard will continue updating. It will reboot again. If reboot failed, wait until 30 minutes. Then force shutdown like before.
6) Now boot again, you should now have leopard updated to 10.5.8. If you use ps2 mouse and keyboard, they might not work again. You need to use usb one.
After update. I notice that leopard failed to recognize my processor. It show up as 4GHz core 2 duo. But it is not a big deal
The main reason I updated to 10.5.8 is new safari requirement.

