Comment 37 for bug 952556

I can confirm that hdparm (9.37-0ubuntu3) indeed didn't fix the issue on Toshiba Laptops; model here is a Satellite C660 with a Seagate Momentus XT 500 GB hybrid HD. The drive is powercycling approximately 3 times per minute on battery and, funnily enough, also when the AC is connected AND the battery is fully charged.
So it seems that the AC adapter is only detected while it's charging the battery, not when it's supplying the power.

Nevertheless I have a (very probably quite embarrassing) problem here: The only item not commented out in my etc/hdparg.config is 'quiet'. Nothing else seems to have been set, or am I missing something here?

As I would be quite happy with not spinning down the HD at all, can I just add 'hdparm -B254' at the end?