Performance issues with new GPU driver

Hi guys, I'm not sure if I should post this in HotS or in the Guild Wars 2 (or AMD?) subreddit.

First I have Acer Aspire TimelineX 3820TG, which is 5 years old but so far I could run almost any game on low (except Watchdogs maybe) and it would run smoothly. 2 days ago I noticed that GW2 is F2P and I downloaded it but when I entered the first map I got 30 FPS tops so I downloaded AMD Catalyst to try to look for new driver. The Catalyst found one and when I started GW2 after that it all looked fine, no lags. I was so happy but when I started HotS yesterday I found out that even in menus I have 20-30 FPS now and in the game it's even worse.

Right now I went back to the old driver so I can play HotS but I really want to play both games and it looks that one driver works fine with one game and the other one with the other game. Can you guys think of any solution for this? The big problem here is that I can't find a place to download older drivers for my GPU from, the only thing I can find is AMD Catalyst which downloads just the newest version of the driver.

Any help is appreciated.