Update successfully (eventually) my rig (simple MacPro3,1, Z77X-UP5 & i7-3770K-HD4000 that's it).
- Copied the Startup partition to a backup partition (just in case).
- Applied the 10.8.3 combo update successfully.
- Restarted and there was no Menu Bar
- Pressed the the Power Button to go to sleep.
- Pressed power again to wake up.....now had the Menu Bar back
- Shutdown and rebooted...no menu bar
- Sleep and wake and shut down.
- Reboot, and installed AppleHDA.kext using kext wizard and restarted
- Have Menu Bar now...All OK
A bit weird but now sorted
Ran Cinebench and the scores went up 20% (from 22 fps to 26)...so some improvement on the HD4000 driver.
Still get the long shutdown/restart times (sometimes 20 secs) that many real Mac users are complaining about...so 10.8.3 has not fixed that issue.