How do I know which R4 card I have? I have the black R4 that says:R4Revolution for DS
(NDSL/NDS)Does that mean it doesn't work with Kingston 4gb micro sd cards?
It's likely an orignal R4, which means it does not support SDHC, and you won't be able to use 4GB MicroSD cards with it, since every 4GB MicroSD produced today is SDHC.