Connect X4 4117 adaptor cannot get throughput on Server 2019 DC more than 10Gbps. Adaptor connected to Dell s5048f-on switch.

HI, I have 2 x Dell R730XD servers each with a 4117 Connect X card, all drivers installed 100%, yet when I run iperf test I cannot get mote than 10Gbps from test. Cables are also rated for 25Gbps. Any idea’s on what to check

Driver Version : 2.60.23957.0

Firmware Version : 14.27.6122

Port Number : 1

Bus Type : PCI-E 8.0 GT/s x8

Link Speed : 25.0 Gbps/Full Duplex

Part Number : 0MRT0D

Serial Number : IL0MRT0D74031998003P

Device Id : 4117

Revision Id : 0

Current MAC Address : B8-59-9F-D1-11-DA

Permanent MAC Address : B8-59-9F-D1-11-DA

Network Status : Connected

Adapter Friendly Name : SLOT 6 Port 1

Port Type : ETH

IPv4 Address #1 :

IPv6 Address #1 : fe80::5ca0:c53f:17e6:dcb2%5

I would suggest that you implement the following steps:

  1. install first the latest Mellanox WInMFT tool in the Win2019 server (

  2. Run “mlxlink” tool PowerShell command to confirm that the actual link of your adapter vs. Dell switch is indeed 25 Gb/s

For example

# mlxlink.bat -d mt4117_pciconf0 -c


Operational Info

State : Active

Physical state : LinkUp

Speed : 25GbE


  1. if 25Gb/s is confirmed, then check with Dell folks if the switch Link-type is properly configured

  2. use the WinOF-2 v2.60 User-Manual to perform driver/fw/pci “performance fine tuning” on the Win2019 win server


  1. Use NTttcp test-tool rather then iperf tool

Iperf tool is more like oriented for Linux whilst NTttcp test-tool is Windows oriented