some CF cards that I have run into have a little switch on the side, that limits the amount of space to 2gb. This was done because some older cameras formatted cards in FAT16 instead of FAT32, and FAT16 can't handle 8gb of space. Is it possible that your card has a switch like this, and that it was mistakenly switched on? check the card, and if it does have a switch like that, switch back, and then reformat in the deck.