Asus TS300-E8-RS4-C - Manual (Page 77)

ASUS TS300-E8-RS4-C 4-21
8. Serial General Purpose Input/Output connector (6-1 pin SGPIO1)
The SGPIO 1 connectors are used for the Intel Rapid Storage Technology
Enterprise SGPIO interface that controls the LED pattern generation, device
information, and general purpose data.
The PSGPIO 1/2 connectors are used for PIKE card.
These connectors function only when you install an ASUS PIKE SAS
RAID card.