Intel i226 network adapter - no 2.5Gbit speed (just 1Gbit)


New Member
Jun 22, 2023
Recently I bought a network adapter with intel i226 chipset. It is a 2.5 Gbit card. I plugged it in my proxmox machine (HP 600 g3 MT) in one of the pcie ports. Unfortunatelly proxmox can't negotiate 2.5 Gbit speed (my router is 2.5 Gbit capable - it's totolink x5000r running 23.05.rc2 openwrt; cat7 lan cable ).
How can I enable 2.5 Gbit speed in proxmox? Network card works at 1Gbit with no issues. What am I doing wrong?
root@proxmox:~# ethtool -i enp3s0
driver: igc
version: 6.2.16-6-pve
firmware-version: 2013:8877
bus-info: 0000:03:00.0
supports-statistics: yes
supports-test: yes
supports-eeprom-access: yes
supports-register-dump: yes
supports-priv-flags: yes
03:00.0 Ethernet controller: Intel Corporation Ethernet Controller I226-V (rev 04)
        Subsystem: Intel Corporation Ethernet Controller I226-V
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx+
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 128 bytes
        Interrupt: pin A routed to IRQ 18
        IOMMU group: 10
        Region 0: Memory at f0100000 (32-bit, non-prefetchable) [size=1M]
        Region 3: Memory at f0200000 (32-bit, non-prefetchable) [size=16K]
        Capabilities: [40] Power Management version 3
                Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
                Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=1 PME-
        Capabilities: [50] MSI: Enable- Count=1/1 Maskable+ 64bit+
                Address: 0000000000000000  Data: 0000
                Masking: 00000000  Pending: 00000000
        Capabilities: [70] MSI-X: Enable+ Count=5 Masked-
                Vector table: BAR=3 offset=00000000
                PBA: BAR=3 offset=00002000
        Capabilities: [a0] Express (v2) Endpoint, MSI 00
                DevCap: MaxPayload 512 bytes, PhantFunc 0, Latency L0s <512ns, L1 <64us
                        ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset+ SlotPowerLimit 0W
                DevCtl: CorrErr+ NonFatalErr+ FatalErr+ UnsupReq+
                        RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+ FLReset-
                        MaxPayload 256 bytes, MaxReadReq 512 bytes
                DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr+ TransPend-
                LnkCap: Port #0, Speed 5GT/s, Width x1, ASPM L1, Exit Latency L1 <4us
                        ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp+
                LnkCtl: ASPM L1 Enabled; RCB 64 bytes, Disabled- CommClk+
                        ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
                LnkSta: Speed 5GT/s, Width x1
                        TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
                DevCap2: Completion Timeout: Range ABCD, TimeoutDis+ NROPrPrP- LTR+
                         10BitTagComp- 10BitTagReq- OBFF Not Supported, ExtFmt- EETLPPrefix-
                         EmergencyPowerReduction Not Supported, EmergencyPowerReductionInit-
                         FRS- TPHComp- ExtTPHComp-
                         AtomicOpsCap: 32bit- 64bit- 128bitCAS-
                DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- LTR+ 10BitTagReq- OBFF Disabled,
                         AtomicOpsCtl: ReqEn-
                LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
                         Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
                         Compliance Preset/De-emphasis: -6dB de-emphasis, 0dB preshoot
                LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete- EqualizationPhase1-
                         EqualizationPhase2- EqualizationPhase3- LinkEqualizationRequest-
                         Retimer- 2Retimers- CrosslinkRes: unsupported
        Capabilities: [100 v2] Advanced Error Reporting
                UESta:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UEMsk:  DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
                UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
                CESta:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- AdvNonFatalErr-
                CEMsk:  RxErr- BadTLP- BadDLLP- Rollover- Timeout- AdvNonFatalErr+
                AERCap: First Error Pointer: 00, ECRCGenCap+ ECRCGenEn- ECRCChkCap+ ECRCChkEn-
                        MultHdrRecCap- MultHdrRecEn- TLPPfxPres- HdrLogCap-
                HeaderLog: 00000000 00000000 00000000 00000000
        Capabilities: [140 v1] Device Serial Number 02-76-c6-ff-ff-00-f3-a0
        Capabilities: [1c0 v1] Latency Tolerance Reporting
                Max snoop latency: 3145728ns
                Max no snoop latency: 3145728ns
        Capabilities: [1f0 v1] Precision Time Measurement
                PTMCap: Requester:+ Responder:- Root:-
                PTMClockGranularity: 4ns
                PTMControl: Enabled:- RootSelected:-
                PTMEffectiveGranularity: Unknown
        Capabilities: [1e0 v1] L1 PM Substates
                L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ ASPM_L1.1+ L1_PM_Substates+
                          PortCommonModeRestoreTime=55us PortTPowerOnTime=70us
                L1SubCtl1: PCI-PM_L1.2- PCI-PM_L1.1- ASPM_L1.2- ASPM_L1.1-
                           T_CommonMode=0us LTR1.2_Threshold=0ns
                L1SubCtl2: T_PwrOn=70us
        Kernel driver in use: igc
        Kernel modules: igc
root@proxmox:~# uname -a
Linux proxmox 6.2.16-6-pve #1 SMP PREEMPT_DYNAMIC PMX 6.2.16-7 (2023-08-01T11:23Z) x86_64 GNU/Linux
root@proxmox:~# dmesg |grep -i igc
[    1.720582] igc 0000:03:00.0: enabling device (0100 -> 0102)
[    1.723835] igc 0000:03:00.0: PCIe PTM not supported by PCIe bus/controller
[    1.764942] igc 0000:03:00.0 (unnamed net_device) (uninitialized): PHC added
[    1.789863] igc 0000:03:00.0: 4.000 Gb/s available PCIe bandwidth (5.0 GT/s PCIe x1 link)
[    1.789867] igc 0000:03:00.0 eth0: MAC: 02:76:c6:xx:xx:xx
[    2.183719] igc 0000:03:00.0 enp3s0: renamed from eth0
[   10.136973] igc 0000:03:00.0 enp3s0: NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
root@proxmox:~# lspci |grep Eth
00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection (5) I219-LM
03:00.0 Ethernet controller: Intel Corporation Ethernet Controller I226-V (rev 04)
root@proxmox:~# cat /etc/network/interfaces
auto lo
iface lo inet loopback

iface enp3s0 inet manual

auto vmbr0
iface vmbr0 inet static
        bridge-ports enp3s0
        bridge-stp off
        bridge-fd 0
root@proxmox:~# ethtool enp3s0
Settings for enp3s0:
        Supported ports: [  ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Supported pause frame use: Symmetric
        Supports auto-negotiation: Yes
        Supported FEC modes: Not reported
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Advertised pause frame use: Symmetric
        Advertised auto-negotiation: Yes
        Advertised FEC modes: Not reported
        Speed: 1000Mb/s
        Duplex: Full
        Auto-negotiation: on
        Port: Twisted Pair
        PHYAD: 0
        Transceiver: internal
        MDI-X: off (auto)
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00000007 (7)
                               drv probe link
        Link detected: yes
When I try to force 2.5Gbit speed via ethtool my network adapter disconnects and I have to reboot my server. I also tried changing lan cables and different router ports with no luck.
ethtool -s enp3s0 autoneg on speed 2500 duplex full
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