What are the laptop graphic card equivalents in performance?

An x1400 GPU for a laptop usually runs at about the speeds of the x1300 PC version. Some cards do stay the same though. The x1400 certainly does not beat a x800xt. The x1400 could play decent games, but with resolution and settings turned down. Friend of mine has a x1300 and plays Battlefield 2 1024x768 on medium, and gets 55 fps. Decent, but it works for him apparently.

No always... some older radeons were a bit decepotive. The mobility 9700 is actually a higher clocked mobility 9600, with four instead of 8 pipelines.

Other than that though, generally laptop parts are architecturally similar to their desktop namesakes, although they often have lower clockspeeds.

Laptops are generally slower than their desktop counterparts, I'd wager a desktop with a 7800 GT would beat a laptop with a 7900 GS without too much trouble, assuming similar CPUs.