diff --git a/src/mainboard/asrock/h77pro4-m/devicetree.cb b/src/mainboard/asrock/h77pro4-m/devicetree.cb
index 581b9a56e2..469567ebf8 100644
--- a/src/mainboard/asrock/h77pro4-m/devicetree.cb
+++ b/src/mainboard/asrock/h77pro4-m/devicetree.cb
@@ -6,7 +6,9 @@ chip northbridge/intel/sandybridge
 		device ref host_bridge on # Host bridge
 			subsystemid 0x1849 0x0100
 		end
-		device ref peg10 on end # PEG - slot "PCIE1"
+		device ref peg10 on # PEG - slot "PCIE1"
+			smbios_slot_desc "SlotTypePciExpressGen3X16" "SlotLengthLong" "PCIE1" "SlotDataBusWidth16X"
+		end
 		device ref igd on # iGPU
 			subsystemid 0x1849 0x0102
 		end
@@ -54,12 +56,14 @@ chip northbridge/intel/sandybridge
 			end
 			device ref pcie_rp1 on # PCIe Port #1 - slot "PCIE4", 4 lanes
 				subsystemid 0x1849 0x1e10
+				smbios_slot_desc "SlotTypePciExpressGen2X4" "SlotLengthLong" "PCIE4" "SlotDataBusWidth4X"
 			end
 			device ref pcie_rp2 off end # PCIe Port #2
 			device ref pcie_rp3 off end # PCIe Port #3
 			device ref pcie_rp4 off end # PCIe Port #4
 			device ref pcie_rp5 on # PCIe Port #5 - slot "PCIE2", 1 lane
 				subsystemid 0x1849 0x1e18
+				smbios_slot_desc "SlotTypePciExpressGen2X1" "SlotLengthShort" "PCIE2" "SlotDataBusWidth1X"
 			end
 			device ref pcie_rp6 on # PCIe Port #6 - RTL8111E GbE
 				subsystemid 0x1849 0x1e1a
@@ -67,6 +71,7 @@ chip northbridge/intel/sandybridge
 			end
 			device ref pcie_rp7 on # PCIe Port #7 - slot "PCIE3", 1 lane
 				subsystemid 0x1849 0x1e16
+				smbios_slot_desc "SlotTypePciExpressGen2X1" "SlotLengthLong" "PCIE3" "SlotDataBusWidth1X"
 			end
 			device ref pcie_rp8 on # PCIe Port #8 - ASM1061 SATA Controller
 				subsystemid 0x1849 0x1e1e