8, 16, 32, or 64 bit: Remember, the higher this number, the better the sound quality. However, the better the sound quality, the higher the price. FM or Wave Table synthesis: The wave table synthesis provides better sound quality, but the FM synthesis is cheaper. Can't decide? Then buy FM synthesis and a wave blaster expansion slot on the sound card. Then if you want to upgrade from FM to wave synthesis, you can buy a wave table daughter board which is a small expansion card that installs right onto your sound card. MIDI port and 3D sound: Generally these are supported on all sound cards. If you are into serious computer game playing, the 3D sound is a must. Voice: which is the total number of tones the sound card uses to produce sounds. The more the better. 20 is a good starting point. Polyphony: is the total number of notes a sound card can play at the same time. Six can produce orchestral sound, and is a good place to start. Multitimbrality: is the number of voices a sound card can play at the same time. The more the better. DSP: which is a special chip on the sound board that frees up the CPU by doing some of the sound processing itself. This will make your sound card work faster. RAM Upgrades: Some sound cards include sockets on the card to add RAM. This allows the card to play more voices and notes at the same time.