D-Link changes product design without changing model numbers. For the DWL-650, they currently have 5 different versions (and this doesn't include the 32-bit Cardbus DWL-650+ versions).
My card is the relatively new Rev. P, which goes back to Prism technology now that Intersil has completed the sale of that business to GlobalspanVirata
The card uses a Prism3 chip.
I was able to get NetStumbler working under Windows 2000, with D-Link's driver, with D-Link's utility, but only in NDIS 5.1 mode. I had to have the utility set the card to Infrastructure mode. If I set the card to AdHoc mode, NetStumbler exits when set to NDIS mode, with nothing reported in the Event Log.