Your CPU might be OK -- although it's not a true quad-core, the i3's HyperThreading might allow it to perform as well (or better) than the minimum Core 2 Quad Q6600. However, your GPU not going to be up to snuff for GTA V. You need something better, like an R7 260X or (much better) an R9 270/270X, provided your PSU can handle it.