Graphics card question

[Breeze]

How's this game run on a ATI Radeon HD 2400?

[Marauders]

Do you have an ATI Radeon HD 2400, or are you thinking of purchasing one?

[Breeze]

Going to buy a new computer, and that's probably the card it'll have.  (actually I can choose the XT or the Pro, no clue which one's better)

[Marauders]

Hmmm, ask them to upgrade to the HD2600.
 
The Radeon HD2400 should run the game, but the Radeon HD2600 is a much better card.
 
With the Radeon, the XT cards are faster clocked than the Pro cards, so if you are given a choice, get the XT card (all other things being equal which isn't always the case).
 
If you can choose between a Radeon HD2400 XT and a Radeon HD2600 Pro, take the HD2600 Pro.  The HD2600 Pro is slower than the HD2600 XT, but it is much faster than the HD2400 XT.
 
These are both DirectX 10 cards, but DirectX 10 features EAT GRAPHICS CARDS ALIVE, so unless you are looking for a $300 card or better, it really doesn't matter much if they are DirectX 10 cards.  In fact, I'd take the last generation Radeon X1650 over the Radeon HD2400 for gaming.