Data speed on MainBoard?

Question

What's the maximum data transfer rate on the mainboard?

Pls. add some links and references..

Answer 1

It is usually at the internal bus that connects processor to Northbridge. AMD's Hypertransport link (3.0) can do up to 20.8GB/s in each direction.
http://en.wikipedia.org/wiki/HyperTransport
Intel's upcoming "Quick Path" is targeting 24 to 32 GB/s per link.
http://en.wikipedia.org/wiki/Intel_QuickPath_Interconnect