FPS Drop after accessing Inventory or Boxes or Looting

There is a huge problem with my FPS, after this new Huge Update.

Game runs very smooth 60+ FPS when i first log on server, it continues to run smooth without FPS drops, but as soon as I access TAB (Inventory) or Box or loot anyone, my FPS Drops by -10 FPS, If i open up Inventory more and more my FPS keeps lowering down to 12 FPS and becomes absolutely unplayable.

Please notice, doesn’t matter if i Play on LOW Graphics (1) or GOOD Graphics (4), Doesn’t matter if i scale Things down or Up in F2 Menu,or Check or Un-check things, FPS just stays there, If i disconnect from Server and re enter the game, My FPS gets fixed again on Solid 60+ until very next Loot or Inventory access.

My friend has almost same spec Computer as i do, and has no particular problems with FPS, my second computer is a total crap, and runs and holds 40+ FPS on low settings and doesen’t LAG after inventory.

My Specs:
Windows 8.1
I5-4570
8GB DDR-3
SSD-Storage
MSI-GTX-560

Especially LAG is furious at Desert (I have house near RAD Town). I think Rust have problems with my Graphics card, doesn’t support it or something, don’t know , all drivers updated e.t.c, I even tried re-installing game, i thought there could be some Cache problem, but it didn’t help at all.

Please reply with anything, this is really game breaking for me.

Thanks

its alpha, the game has little to no optimization, deal with it