Motherboard Memory slot question

[sweave]

saw this in the memory slot description section for a motherboard i was looking at

Memory Expansion
The KN3 SLI2 (1.0) provides 4 DIMM sockets using Dual Channel 240-pin DDR2 with a total capacity of up to 4GB (32GB-64bit). You can install DDR2 400/533/667/800MHz Memory.

what does it mean by 32gb in 64bit mode?

thanks

[primesuspect]

If you are running a 64bit OS, your motherboard will support up to 32gb of ram. With a 32bit OS, you are limited to "only" 4gb :)