Do you use torrents? You can download packs of the games, there usually set out like this: the first pack will be the first 1-1000 games, then the next will be 1000-2000, so on, some maybe in 500’s, but you can get them via torrents, also, depending on the size of the card you get, you’ll only be able to put on around 5 on at a time, and if u get bored of those, u drag them off and another 5 go on, so on and so forth.
sites like this: http://nds-roms.com/ will also provide roms.