Will a video card not on a game's supported cards list work?

I recently decided to upgrade my computer's video card to an ATI Radeon X1550, not only to update the looks of my older games, but to make new ones accessible to me. I was looking at the supported cards list for the Spore Creature Creator, and it had what appeared to be most of the ATI Radeon X-series, but not the X1550. Also, I don't want to buy a new card that won't work on new games I buy. Is this still a good card, and will it cause problems if it's not on the list? My dad (A computer-genius-man) said it shouldn't but I just wanted to make sure.|||Yes it will work. Supported cards in a list are usually mentioned as advertisement due to their sponsorship towards a game.|||if your dad truly is a computer genius then why don't you believe him? wtf???