Intel Drivers (under Graphics - note that this took me two clicks to find)
Simple answer, as veb has already stated: If you set shaders to 1 with all of the other Premium Graphics features set to 0, and no shaders appear, it's time to upgrade.
"Call yourself alive? I promise you you'll be deafened by dust falling on the furniture,
you'll feel your eyebrows turning to two gashes, and your shoulder blades will ache for want of wings."