Asus Z9PA-U8 - Manual (Page 36)

2-16 Chapter 2: Hardware information
2.5.6 PIKE slot
The PIKE slot allows you to choose and change your preferred SAS solution
easily. Install an optional ASUS PIKE RAID card based on your needs.
Slot No. Slot Description
7 MIO1 (Only for Audio)
6 PCI-E x16 (x16 Gen3 Link) (Audio switch to x8 Link if slot 5 is occupied)
5 PCI-E x8 (x8 Gen3 Link)
4 PCI-E x16 (x16 Gen3 Link) (Audio switch to x8 Link if slot 3 is occupied)
3 PCI-E x8 (x8 Gen3 Link)
2 PCI
1 PCI-E x8 (x4 Gen2 Link)