|My HP DV6 has an i7 720QM running at 1.6ghz clock.|
However, when I plug in a charger, this drops to a constant 928MHz.
When I pull the charger out, and it's running on battery, this goes back up to 1600MHz and becomes more variable depending on the activity.
I've checked using CPU-Z and it actually is being underclocked everytime I plug in a charger, I have no idea why.
The difference is very noticeable when I'm playing games, I can play the new Medal of Honor on high text and AA when unplugged, but only on Medium no AA when plugged in.