MacBook SMC Firmware update (#2): Lower temperatures, louder fans; Does not resolve sudden shutdown issue
MacBook SMC Firmware update (#2): Lower temperatures, louder fans; Does not resolve sudden shutdown issue
We are beginning to receive initial feedback on the SMC (system management controller) firmware update for MacBooks (13") issued yesterday.
The general consensus is that this update brings overall lower operating temperature through increased use of the fans -- also resulting in generally noisier operation.
Some users also report alleviation of the infamous "mooing" noise generated by some MacBooks.
MacFixIt reader Peter writes:
"The mooing noise too effect between 65-67 degrees Celsius previously -- low pitch fan noise on and off at that level. And my fan only started at full speed (LOUD) around 72-78 degrees Celsius -- that only happened when I did compilation of a build.
"Now yes the temperature reading on CoreDuoTemp is about 8 degrees Celsius lower, and the low pitch mooing noise disappear, but now the Fan was turned on much louder at much lower temperature at the same CPU workload as before.
"Now even when each of the dual core CPU is about 80% idle, at temperature between 55-60 degrees Celsius, the fan is at medium to full speed (very loud)."
MacFixIt reader Danlich adds:
"The firmware update has gotten rid of the recurring 'moo' on my 3 day old white MacBook 2GHz. The 'mooing' is, instead, replaced by a quiet but constant drone of the fan. I'm kind of sad about this; I thought the moo was a charming characteristic of this computer."
UPDATE: Does not resolve sudden shutdown issue Several readers indicate that this SMC firmware update does not resolve an issue we've reported where MacBooks suddenly shutdown.
Our previously noted solutions for this issue (aside from sending units in for repair) include re-seating RAM, removing certain .plist files.
Feedback? Late-breakers@macfixit.com.
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