Funny that oldandslow mentioned the word fry.

While trying something not too different from what you're wanting to do, a technician thought that he had the right pin-outs and stuck my 128mb stick into the USB. No reaction from the PC, no 'new hardware found'. We pulled the stick out and, lo and behold, we smelled something not too different from the smell of a burnt match. Hence, the word fry.

Moral of the story: I'd spend the couple of bucks for the PCI USB card.