Using In built graphics is a massive no, no. If you did manage to load into the game, you would be looking at 10fps or lower, which is unplayable. With that setup you should easily be able to max the game, im running on Very high (max setting) using a R9 280x which is slower than the 770.
You wont get that speed, contact your Internet Service Provider (ISP) about getting a better net package. Will cost more money, and may not improve depending on your location.
I too get issues like this, a couple of months back i could run the game fine with no frame drop at all, however recently (And since i updated my graphics drivers) i have noticed a significant drop in performance :/