Differeces between Unbuffer & Registered PC2100 DDR ???

[Ti]

Hello everyone, I just bought a dfi ak76-sn mobo yesterday and planning to buy 256mb ddr2100 for the mobo, but i don't know which one to buy either the unbuffer or the registered one, can anyone please tell me the different between the two ? i notice there's only a slidely different in price for the two.
Best Regards.

PS: if anyone in here have the DFI-ak76-sn please feel free to share you opinions about the mobo.

 

[Parser]

Unbuffered is normal RAM for home use while registered and ECC RAM are for servers. Most motherboard won't even accept the registered or ECC RAM and those that do take a slight performance hit from it. Basically if your not using your comp as a server get unbuffered.