|I found a picture of one on ebay:|
The ct2502-sdq is on the chip. The card model number is in the corner of the card. I can't quite make it out in that picture but it looks to be ct-2940 or ct-2040. Yours may be different as creative uses the same chipset for different models.
As you can see there's a lot of other stuff written on that chip that makes no sense to anyone but the manufacturer and card assembler. Usually when someone gets a PC card they just want drivers for it. For that you look first at the card model number. If that doesn't pan out then you can google the chipset, ct2502. The sdq might--but probably doesn't--affect what drivers you'd use.
It's often hard to find info on cards on creative's site. Some are because they're OEM and creative doesn't support them. Others, well I don't know, I think maybe they just want to make it difficult. But if you find any info for that card on their site it won't be under 'ct2502-sdq'. It'll be under whatever the ct number is in the corner of the card.
But if the link in my # 1 is correct then it uses vibra 16 drivers.
If you still want to know exactly what the 'sdq' means you'd have to locate a spec sheet for that chip.