Ati hybrid graphics ati+ati Stutter in some games

[arabcian]

Hi im sorry for my bad english

Currently im having some stuttering problems with some games with my asus k53ta laptop
all hardware on my laptop recognized by kernel and working

im having better performance on Doom3 and Torchlight game on internal gpu which is 6520g im getting %100 gpu usage while gaming and %30 cpu usage, game uses only one core but if i have turn on dedicated gpu which is hd6650m ddr3 im getting sluggish gameplay cpu usage is %30 but gpu usage never reaches above %25 there is no bottleneck in the system has good benchmark scores

but the problem is not for every game i play if i play amnesia dark descent dedicated gpu performance is bettter than internal gpu performance i tried every possible setting variation on amd control center and have no success on torchlight and doom3 what could be the problem bad coded engine? or my system configuration is bad?

can anyone help me? thanks...

My system is gentoo-sources 3.4.9 amd64 kernel
Cpu amd a6-3400m quad core with integrated radeon 6520g
dedicated gpu is hd6650m
My cpu is overclocked to 2.7 ghz
using 12.9_beta ati-drivers
clocksource is tsc dynamic tics disabled 250hz resolution timer
io scheduler is cfq

i tried adding custom profiles to atiogl.xml file
forced performance governor
disabling enabling vsync

with no luck.

any ideas welcome