Intel Core- i3
8 GB Ram
Intel HD Graphics 4400
64-bit
Hey Sinister,
Can your rig run Overwatch? Yes.
Will it be super pretty? Probably not.
The CPU and GPU are both right on the edge of the minimum system requirements. It should be possible to launch the client, but the graphics settings will need to be fairly low for stable gameplay. You can find the system requirements here.
-Lantrasau
If I buy a GTX 660, will it increase good gameplay?
It will but you also should consider upgrading to an i5-core processor as well.