TYAN S5548GM4NED83-4T Manual page 95

Link Speed
Choose Link Speed for this PCIe port
Auto / Gen1 (2.5GT/s) / Gen2 (5GT/s) / Gen3 (8 GT/s)
PCI-E Port Max Payload Size
Set Maxpayload size to 256B if possible
128B / 256B / Auto
PCI-E ASPM Support
This option enables / disables the ASPM (L1) support for the downstream devices.
Auto / L1 Only / Disabled
L0s Support
When disabled, IIO never puts its transmitter in L0s state
Disabled / Enabled
Hide Port
User can force to hide this root port from OS
NO / Yes
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