200GbE Smart NIC Card for Mellanox MCX653106A-HDAT-SP, PCIe 3.0/4.0 x16 200Gb VPI Ethernet NIC with Mellanox ConnectX-6 Dx Chipset,Dual QSFP56 HDR IB Network Card Support RDMA

I've bought around sixteen of these and they've all been solid. I don't have any brands/models to compare them to. So, I don't know if they could be any better. Nevertheless, I'm getting pretty close to full 25GiB in speed tests. I'm using these with Mikrotik switches and 10Gtek transceivers.

No problems

Used two of these to connect between my NAS and desktop PC. Both machines are running on Windows and neither had an issue working as soon as the network card was installed. My devices are relatively close so I am currently using DAC cables.In testing a file share in between my NVMe drive on the NAS and local PC I was able to get a transfer speed of 2.24GB/s, around 2,240 MB/s or ~19Gbps without any network adjustment or tuning whatsoever. The NVMe drives should be a bit faster than that but this was good enough for me, until I get more remote NVMe storage only a fraction of my data is available at these speeds anyways.HardwareIDs below as reported from device managerPCI\VEN_15B3&DEV_1015&SUBSYS_006915B3&REV_00PCI\VEN_15B3&DEV_1015&SUBSYS_006915B3PCI\VEN_15B3&DEV_1015&CC_020000PCI\VEN_15B3&DEV_1015&CC_0200

Installed and worked perfect.

My first purchase was made on Aug 2024, it was a decent product with a nondescript package. The confusion comes when I was updating the firmware. The site claims the model to be MCX4121A-ACAT but I found it was detected as MCX4121A-ACUT, U for UEFI. This card has worked fine although I could not figure out how iscsi wouldn't work in BIOS. It works fine in windows but that is a different story. The speed in iperf3 comes at around 19.2-23.4 Gbps.I purchased the second time just recently in Mar 2025 and found that packaging and construction have become all different. Now it is clearly labelled as an ACAT model while still claiming UEFI functionality which caused further confusion. I ended up returning the second item without testing and switched to something different.

One of the few 10GB variations that works natively in Proxmox. I bought 3 of these.

Compatibility: I'm using Windows 10 Pro with a 13th Gen Intel system, no problems.Functionality: Works fine, does get warm, so make sure to have good airflow.Ease of installation: I'm using Windows 10 Pro, and it's a simple plug and play.Speed: Can't verify full speeds, as I only have 2.5GbE, but easily reaches 2.5GbE speeds easily.Design: Simple, but decent design.Value for money: Great value for money.

Started with an internal firmware issue - card is broken no reset or successful installation of firmware can address this (so far)