Are you sure it's the card?When I use TAB to check my stuff I find that I still only sue half of the card's memory or so.If there are issues with your game's performance and you are not using all of the memory in your card it could be x10.
FPSC (either version...original or extra next gen) seems to develop problems specifically related to one's pc.In other words you can run FPSC on 10 different pcs and get 10 different results.
x10 seems to run more uniformly across pcs.
I am sorry to hear you might have to get another card.
On the bright side your pc didn't fry so it could have been worse and the price of cards are dropping all of the time.
I had to get the card I got because it was the only x10 card that would fit in my machine.
But when I get done building my UberComputer it will be state of the art...for about 5 minutes until the next batch of stuff comes out...
RIP Floating Skull unknown-2007 we will miss you in FPSC x10