Thu Oct 18, 2012 9:00 pm
Firstoff, I think you mean gigabytes (GB are 1048576 KB, MB are 1024 KB). SD card sizes generally range from 256MB to 64GB (although they do manufacture 128GB and 256GB cards).
If you wish to install the OS directly on the SD card, it must be generally 2GB or more (but 2GB fills up fast). If you wish to put only the boot partition on the SD card and put the OS on a separate USB drive, the card can be as small as 64MB.
Raspberry Pi generally can support all SD cards.
{sig} Setup: Original version Raspberry Pi (B, rev1, 256MB), Dell 2001FP monitor (1600x1200), 8GB Class 4 SD Card with Raspbian and XBMC, DD-WRT wireless bridge