I am not sure what my GFX card on my work computer is, but I got it 2 weeks ago so it is fairly good.
Uhh.. they didn't stop selling crappy videocards in the past two weeks.
So you have nothing else going on but this lightmapped terrain, and you're down to 30fps? If so, can you post the whole code? There shouldn't be too much to it if it's just a terrain.