I've made some changes in the Catalyst Control Center and the game seems to run more fluently now. Mostly, I told it to bypass all SWTOR settings in order to do what I chose (max quality all the time). However, I haven't tried it in an 8 man operation yet.
Thanks for answering this post, here are a few answers:
Nowadays, laptops can be very powerful. Mine can run any game with ultra specs: any game. SWTOR should make no difference.
My problem is not lag (latency problem) but frame per second problem. It happens only when lots of things are going on (engaging fights). No problem on Carrick station for example.
My FPS always goes from green to red in a very fast way.
Good advice, anyone should take it. Thanks !
CTRL + SHIFT + F = your FPS in the lower left corner of the screen.