Horrible FPS in games that I used to run fine.

Hi!
Not sure if this is the right spot or not, so im sorry if it's incorrect.

I have an Alienware MX15 from a few years ago, equipped with an i5.
It used to run most if not all the games i tried, very smooth.
Now, as of maybe ealry this year, everything runs at a good 15-20 fps.
Examples being, Guild Wars 2 and Final Fantasy 14.

It's wierd, because i have run Basic Catzilla Benchmark, along with a few other tests, saying my system should be WELL able to handle these games.
I am leaning towards it being a problem with my processor. I have reseated it, with new thermal compound, and cleaned the inside. That used to fix it, but not this time.
Ive reformated, Bought a new hard Drive (SSD) and done a malware scan.

any tips? I'm just lost... ive been working on it for almost a year, and i just gave up.
But now im fed up and want to play my games again!
Thanks everyone!

Here is my setup

alienware MX15
Bios version A08 1.00
Intel i5 CPU M540 @2.53GHz (4 CPUs) ~2.5GHz
Memory 4096mb RAM
DX11
AMD Mobility Radeon HD 5000
2769mb

Im running Windows 7 64bit

 

Found this guide in GW2 tech forums
https://forum-en.guildwars2.com/forum/support/support/PC-FPS-and-Performance-based-issues
and some suggestions here
http://www.pcadvisor.co.uk/how-to/game/how-improve-fps-image-3489433/

Generally, keep drivers up to date, adjust GPU settings, and game graphic settings. Check game tech support forums for FPS threads, you can relate to.