Hello I show that we limited slots 1 and 2 to gen2 because of issues encountered when they were set to gen3. The notes I have read suggest that the mezzanine slot will still operate at gen3. As mentioned in the linked article, only Dell custom mezzanines are supported in the mezzanine slot. I had difficulty locating the mezzanine card that you have installed. I located the model on Mellanox's site: [URL] I checked part 540-BBKI and found that it contained card part # 79DJ3. That card is not listed under the part list of the C6220. It does not appear to be supported in the system. Thanks
I've read this: [URL] I'm trying to see why a Mellanox MCX-353A-FCBT (Gen3 x8) card, installed in the mezzanine slot is capped to 4GB/s throughput on an (old) PE C6220 motherboard. The mezzanine slot on that motherboard is called SLOT1_PCIE_G3_X16(CPU1). System tools (lspci -nvv -s 3:0.0) show that PCIe link training does indeed occur at 5GT/s (Gen2), which would be a cause for exactly this limit (at x8). In the link above, there is a mention of "the exception of the mezzanine slot, which only supports Dell custom mezzanine cards". What cards are concerned by this exception ? The Mellanox card, which was purchased from Dell with the server, is clearly listed among the supported add-in cards in a Dell document called "PowerEdge C6220 Technical Guide", dated december 2013. Should I understand that this document was wrong, and that the hardware has a design flaw which is the culprit behind my underperforming Mellanox card ? Best regards, E.
PE C6220 PCIe Gen3 link