Kitty is so right here.
the omega drivers more than doubled my FPS in F.E.A.R.
the Installation is so simple
download the omega driver from www.omegadrivers.net
use the ATI uninstall utility in control panel/add-remove programs
allow the system to reboot
Make sure that the uninstaller has removed catalyst control centre.
install the omega drivers, following the onscreen instructions carefully.
reboot again at the end, and the system will be back to better than normal.
The only thing I have noticed, is that the card runs warmer with the omega drivers, so that would explain why acer restricted their included drivers, to keep the machine cooler,
I can see the machine becoming uncomfortable on your lap. and as someone posted on another thread, get extrememly warm with the lid closed when used as a desktop replacement.