Issues, Workarounds & Localization

Hello everyone, I've returned to EVE when Odyssey came out and since then I've been having very weird FPS issues. When I play for about 2-3 hours(apparently now it's random!) not restarting the game client, FPS drops in general and especially there is HUGE drops from stable 30-40 60 fps to 1-3 fps whenever my weapons finish reloading. There's also less noticeable drops(for a split second) on other actions like opening radial menu and other things like that. When i restart the game client this issue disappears for 2-3 hours and then it's starting to do this thing again. I never had anything like this in other games. The thing is my GPU isn't overheating and for the first 2-3 hours game is running smother than anything on the relatively high graphic settings at 60 FPS stable.
My specs are here:
OS Windows 7 Ultimate edition x64
CPU AMD Althon II X4 640 3.0 GHz
RAM 16GB
GPU Sapphire HD 7950

I've googled it and found nothing similar to my problem(with weapons reloading dropping FPS). Also changing graphic setting doesn't change anything, the issue is still here no matter what I'm using - maximum quality setting or minimum quality.
Hope it's not hardware problems, because I want to move from high-sec and will not be able to restart my client so often AND don't have money to upgrade my hardware either...

EDIT: Bought a new GPU recently, for some time the game wasn't doing this weird thing, but today it happened on my first mission i've done 20 mins after i launched the game. Don't know what causes this, but it's not GPU for sure.