Asus Motherboard DSBV-D - Manual (Page 46)

2-26 Chapter 2: Hardware information
2.5.6 PCI Express x8 slot (x4 link)
The onboard PCI Express x8 slot provides x4 link to the ESB. This slot is designed
for various server class high performance I/O add-on cards like SCSI RAID card,
fiber-channel card, etc.
PCI Express x8 slot
2.5.7 PCI Express x16 slot (x8 link)
This motherboard supports PCI Express I/O cards that comply with the PCI
Express specifications.
PCI Express x16 slot