我應該找到答案了...

http://www.beyond3d.com/previews/at...0/index.php?p=2


in total the RS480 houses 22 PCI Express lanes. RS480 doesn't integrate any Gigabit LAN capabilities as ATI suggest motherboard vendors are keen to seek out their own solutions, so ATI has left 4 PCI Express lanes in the Northbridge so that a PCI Express Gigabit LAN device can utilise them. There is a further two PCI Express lanes allocated for connection to other Southbridge's


1.RS480控制22條lanes是確定的
2.扣掉16x *1和1x *4,
北橋還剩下兩條lanes可供運用--似乎是拿去連接南北橋

不過還是需要高手鑑定一下,我會去k英文的技術資料...