I think the problem is your OS (Operating System). By your specification, your system is not ready for Win10!!
My PC:
AMD Quad-Core A10-4655M APU (4x2Ghz)
AMD Radeon HD 7620G + HD 8670M Dual Graphics
1 TB SSD
12 GB RAM
Windows 7 Ultimate x64 bits
It runs the game smoothly with 0 lag, but if i put win 10 the game lags, get errors, and it's nearly impossible to play, and in other games it lags and i can't play any type of game!! My system don't support win 8/8.1/10, if i put anyone of these OSs my system becomes slow, i put win 7 ultimate 64 bits and my pc becomes a rocket!! Said that i know that Win7 has no support but for me it's the best OS for now!!