Can I use a 60w charger from a 13" macbook pro to charge a 15" macbook pro? (i believe the 15" uses a 85w charger)
Mac Pro, Mac OS X (10.7.3)
Yes you can but it will only charge the unit when it is powered down. It won't charge and run it at the same time.
15" and 17" MBPs use the large 85 watt power adapter.
So, of the computer is powered on, the adapter will be overloaded and may get damaged, and there won't be enough juice so the battery will slowly drain.
If the computer is powered off, who knows what will happen. It may charge or it may get overloaded and get damaged. The 13" has a 63.5 W/Hr battery, the 15" has a 77.5 W/Hr battery; will that difference be significant, besides a longer charging time?
Read this: http://support.apple.com/kb/HT2346. You really need to use the correct charger.
Ok thanks
I found the following post to give a plausible explination. Basicly with a computur that needs 85w using 60w may cause intermitant charging with heavy cpu use, for a computer needing 60w using a 85w will not cause problems as the 85w adapter can change output.
That page really isn't helpful because it doesn't explain anything.
60w Charger to charge a 15" macbook pro?
