diff --git a/src/mainboard/siemens/mc_ehl/variants/mc_ehl6/devicetree.cb b/src/mainboard/siemens/mc_ehl/variants/mc_ehl6/devicetree.cb
index c6861401c0..5180770908 100644
--- a/src/mainboard/siemens/mc_ehl/variants/mc_ehl6/devicetree.cb
+++ b/src/mainboard/siemens/mc_ehl/variants/mc_ehl6/devicetree.cb
@@ -75,6 +75,9 @@ chip soc/intel/elkhartlake
 	register "PciePtm[4]" = "true"
 	register "PciePtm[6]" = "true"
 
+	# Determine PCIe root port speed
+	register "PcieRpPcieSpeed[6]" = "2"
+
 	# Storage (SATA/SDCARD/EMMC) related UPDs
 	register "SataSalpSupport" = "0"
 	register "SataPortsEnable[1]" = "1"