Asus P5MT-C - Manual (Page 37)

ASUS P5MT-C 2-17
2.5.5 PCI slots
The PCI slots support cards such as
a LAN card, SCSI card, USB card, and
other cards that comply with PCI 2.3
specifications. The figure shows a LAN
card installed on a 32-bit PCI slot.
2.5.4 PCI Express x8 slots
This motherboard supports PCI Express x8 network cards, SCSI cards, and
other cards that comply with PCI Express 1.0 specifications.
PCI Express x8 slot1
(x4 link)
A PCI Express card inserted to the labeled PCIE1 slot may run only at x4
speed due to chipset limitation.
PCI Express x8 slot2
(x8 link)