unusual FPS drop (down to the sup 10s)

i know that people have said that they have massive dps dorps with high end PCs before and other people said that the game is not optimised for high end PCs because its an old client and all but my specs are not that high but mid / below mid
the problem is that my fps drop to 25~ all the way from 70-90+ every few seconds in when i'm in a non preformance intensive places like the cave that you spawn in after you TP to thunder bluff or even when i'm standing still and not moving.

in raids its even worse with all low settings and the bare minimum addons that are needed to raid i cant even get 50 fps, mostly 30 to 40 and when ever i get in combat no matter if its a boss or a trash pack it drops to 15~ every few sec and some times even 7 or 10 fps.

specs are 6 GM ram and intel r hd graphics 3000 and intel i5 and yes i have all my drivers updated and iam running the game on lowest settings possible and nothing else opened with it other than 1 tap of google chrome with discord on it
is there anyway to fix this?

You will not have a good experience with an integrated graphics processor, period.
The game runs on directx9 api, which isn't great at all these days(unless you're running a "time capsule" machine with <win8.1 and a bit older drivers).
Also, discord has hardware acceleration option, if that's turned on, then it adds to your problem.
Chrome can also utilize the gpu for whatever task, that's yet another factor.
You don't have much of a choice. On wrath if you're in a populated area or a 20man+ raid with high amount of textures/particles for processing, it's gonna be like this.