PCIe slots and PCIe adapters
This topic provides installation rules for PCIe adapters.
Slot configurations
The following lists the PCIe slot configurations for each server view.
*E: empty
Server view PCIe slots
Slots 1–3 on riser 1: 
•  x16/x8/x8 (Gen 4/5)
•  x16/x16/E (Gen 4/5)
•  E/x16 (Gen 4/5)/x16 (Gen 4)
Slots 4–6 on riser 2: 
•  x16/x8/x8 (Gen 4/5)
•  x16/x16/E (Gen 4/5)
•  E/x16 (Gen 4/5)/x16 (Gen 4)
Slots 7–8 on riser 3: 
•  x16/x16 (Gen 4/5)
•  x8/x8 (Gen 4/5)
Slots 1–3 on riser 1: 
•  x16/x8/x8 (Gen 4/5)
•  x16/x16/E (Gen 4/5)
•  E/x16 (Gen 4/5)/x16 (Gen 4)
Slots 4–6 on riser 2: 
•  x16/x8/x8 (Gen 4/5)
•  x16/x16/E (Gen 4/5)
•  E/x16 (Gen 4/5)/x16 (Gen 4)
Slots 7–8 on riser 3: 
•  x8 (Gen 5)
Slot 9 on riser 4: 
•  x8 (Gen 4)
Slot 10 on riser 4: 
•  x8 (Gen 4/5)
54 ThinkSystem SR665 V3 User Guide