Suggestions for video card Intel MicroATX

My son has a Gateway with an Intel MicroATX motherboard. Running Vista
Home Premium 32 bit.

The processor seems to be adequate, Core2 duo. But the on-board video is
terribly inadequate for games.

There is a slot for a PCIe x16 card.

The question is which one to get?

I've been running Athlons and ATI for so long that I haven't kept up
with what matches well on the Intel side.

Any helpful suggestions are appreciated. I do have a month or so to do
research.

Thanks,

Tinker