Basically as long as your GPU is capable of transfering a readable signal from your computer to your monitor it's capable of running AE. Performance-wise you might need to ask different questions that not only involve your GPU.
It's too old to have any meaningful influence on hardware acceleration features, but as Klaus said, yes, AE wil run on a system with it. It may just not be much fun.
As the others say, that GPU won't be used for some specific features (most notably GPU acceleration of the ray-traced 3D renderer), but that is not relevant to most of the features in After Effects.
See this page about what the GPU is used for in After Effects: