This seemed to happen after I did several things at once (all of which I have since reversed in trying to track this down):
- installed a (Crucial M4) SSD drive (replacing my old SATA 5400 RPM drive),
- upgraded from 2GB RAM to 4GB, and
- upgraded to Mountain Lion (from Snow Leopard)
For weeks I've been trying to track down what the problem could be. I've read all sorts of things about Mountain Lion using more power and various conflicting things on the Crucial forums about whether or not their SSDs consume more or less power (SSDs are generally advertised as being less power-hungry but there are a few conflicting reports!).
Anyway, I'm now back to my old SATA drive, my original 2 GB RAM and a completely clean install of Snow Leopard. But I still have a reduced battery life and I can't figure out why.
Where I'm at now is that the milliAmps consumed by my MacBook when it is pretty much completely idle (i.e. 1-3% CPU usage in Activity Monitor, All Processes) it is consuming about
925 mA (according to System Profiler)
It fluctuates, but often goes up above 1400 mA and never lower than 750 mA. I never paid attention to this value before but I know two things:
- I used to get > 6 hours battery life in normal usage (emails, browsing) and now I get < 4.
- My friend's MacBook idles at around 450 mA.
My fan speed is 1800rpm during this normal usage.
Any ideas how I can solve this?