Dare, NFS:SA's FPS scale directly with your CPU's single thread performance.
That means, regardless of GPU, a strong CPU is what will make your FPS stable, at least it's the one that counts for it the most.
A fast HDD/SSD is also important to kill the stuttering you experience sometimes.
In general, MTA is not taxing on the GPU much, and, for it, it's nowhere as important as the CPU.
However, it's good that you have at least 2GB of VRAM.