I was able to update my Hacintosh to 10.6.5 (from 10.6.3) by simply downloading and installing the 10.6.5 Combo Update. The Hac rebooted fine and the graphics worked fine. I was even able to install subsequent updates without any problem.
But then I decided to try fixing my Insignia Keychain Picture thingy which required booting up in 32-bit mode. (See the previous post for the details.) Doing that meant setting boot flags and I forgot, as usual, to use the “-f” to tell it to not use the cached kexts. That caused a kernel panic. I was able to boot again right away without the i386 flag and the computer started up as usual. But I tried again with the i386 flag and the -f flag and I got the blue screen freeze. It worked on my second attempt, though. And I was able to do what I needed to do in 32-bit mode. So I rebooted again, using the -f flag but no architecture flags so it could return to normal 64-bit mode. I got the blue screen again. A second time and I got the login screen but it hung. A third time and it hung. Uh-oh.
I tried a couple of other things like booting into single user and taking out the NV Enabler kext. Nope. I tried looking at the filesystem of my Hac from my Windows computer and I could actually see the files so I knew the computer was up – I just couldn’t interact with it. As I was puzzling over this, the graphics started working again. I was able to put NV Enabler back in and regain the QE/CI capabilities. Rebooting works fine now and all appears back to the way it was before I messed around with the boot flags.
So what happened? As usual, I don’t know. But here’s a guess: Perhaps even though the computer comes up with a blue screen and/or a frozen screen, it actually isn’t really stuck; it’s going super slow after the cache has been cleared. And maybe the best thing to do is to just walk away for 15 minutes and see what happens while you are gone. Hopefully I remember to read this post the next time it happens to me.