要看設計..
不過這樣做是可以的...
除非他反而去跟PCI借...

依照描述的話:
PCI Express*
—6 PCI Express root ports
—Supports PCI Express 1.1
—Ports 1-4 can be statically configured as 4x1,
or 1x4
—Support for full 2.5 Gb/s bandwidth in each
direction per x1 lane
—Module based Hot-Plug supported (e.g.,
ExpressCard*)

There are six root ports available in ICH10. These all reside in device 28, and take
function 0 – 5. Port 1 is function 0, port 2 is function 1, port 3 is function 2, port 4 is
function 3, port 5 is function 4, and port 6 is function 5.
PCI Express Root Ports 1-4 can be statically configured as four x1 Ports or ganged
together to form one x4 port. Ports 5 and 6 can only be used as two x1 ports.