Just as i wanted to present my solution, mod closed the thread
Ok, i decided to buy 2nd hand core2 duo 3.16ghz (70euro) and put it instead of my 2.4ghz c2duo. And my swtor experience jumped up by 100%. i can finally pvp normally with 25-30fps average (had around 15), same with fleet - fps there is about 25. Not to mention other things - pvp and fleet were worst by performance. And saved 400euro at least
thnx everybody for such nice thread and help