I would just spend up on the i3 since you get also a faster CPU and better performance with the money spent.
A video card that would do good 3D and not too expensive will cost the difference of an i3 and a lower CPU like a Pentium. A good card choice would be a RADEON 6570 (under $50) if you really wanted one.
If you want to save money and don't mind a weak CPU then just get an AMD chip and skip the video card all together. Many AMD chips are cheaper than i3 and have better graphics and 3D.
A video card that would do good 3D and not too expensive will cost the difference of an i3 and a lower CPU like a Pentium. A good card choice would be a RADEON 6570 (under $50) if you really wanted one.
If you want to save money and don't mind a weak CPU then just get an AMD chip and skip the video card all together. Many AMD chips are cheaper than i3 and have better graphics and 3D.