Yeah, I would primarily stick to slightly older games. Most PC games from the PS3/360 era would likely run fairly well on that system. GTAV was originally released for those consoles, but it was between generations and the PC version is more like the XBONE/PS4 release, and probably wouldn't run all that well on that hardware. That said, I think your system
technically meets the game's minimum requirements. Going by the
minimum requirements listed on Steam, they call for a Radeon HD 4870, which is similar in performance to an HD 5750/5770, a Phenom 9850, which should actually be a bit slower than a Phenom II X4 955, and 4GB of RAM. I suspect those might be the requirements to run the game at 720p resolution at low settings though, and that hardware probably won't run it particularly smoothly.