The new SMC and EFI firmware updates for the various "Late 2008" (unibody) MacBook models have, for the most part, installed and worked properly. Users have reported the resolution of various issues, and the relativel scarcity of questions on the Apple Discussion boards indicates that the updates are, generally, working as they should.
Still, there have been one or two people for whom the updates have introduced new problems. One user had a Siig eSata expresscard for connecting some external hard drives, but after the firmware update the card is no longer working. Another user found problems with his displays not properly switching when he plugs in an external monitor. It seems that the computer now will not recover the original display after unplugging an external monitor. If users are experiencing either these or other problems after applying the firmware updates, please let us know.
Users who are experiencing problems after these updates are installed should try resetting the computer's PRAM and resetting the System Manamgement Controller (both quite relevant to these updates).
- PRAM: Reboot and immediately hold the options-command-P-R keys down. The computer will continually reset and make the boot chimes while these keys are held, and users should allow it to cycle 2-3 times before releasing the keys and allowing the computer to boot normally.
- SMC: Power off the computer and remove all power sources (Battery and AC adaptor). Then press and hold the power button for 5-10 seconds. Re-attach the power sources and start the computer back up again.
Aside from direct hardware problems, one user found that his networked Time Machine disk image backups would no longer mount. However, this situation was addressed by mounting the disk image in Disk Utility and repairing the file system. Most likely this was not directly caused by the firmware updates, but there's always the possibility that some change could spur a previously unstable situation into failure.
Beyond these relatively few problem reports, the updates appear to not address a few prevalent problems, namely displays problems. For a while users have been plagued by screen flashes on their new machines, and this seems to persist. Additionally, folks attaching external displays still seem to be getting graphics artifacts or go black for a while. These problems may be a driver issue, and hopefully will be addressed with the upcoming release of OS X 10.5.6.