Tons of options out there with that, but you presumably want cheap.
Always. Good, Cheap. Pick one

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That's not happening currently. The motherboard discussed in this thread was a custom SKU built specifically for Softlayer. They likely realized that there were more economical options out there on newer generations of hardware that negated the need for the sizable capital expense of paying an OEM to design another motherboard.
And the Supermicro X10SLL-F/X10SLM-F was one of my main favorite Platform (technically still is) so the X10SLH-LN6TF is from the same "Family".
That's why I'm surprised at the HUGE Idle Power Consumption of this X10SLH-LN6TF.
I suspect nobody checked ASPM support being Enabled and supported by all the Hardware, at least there was not mention of ASPM at all in this Thread.
That's why I believe that the Power Consumption is so high. The X10SLL-F eats I think around 25W at almost Idle. And the X10SLL-F had a finicky BIOS Bug with FADT Tables, so you need to patch those in a custom initramfs (or a pre-initramfs so to speak) to force ASPM on.
It cannot be that the X540 eat 35W while doing nothing !
Apparently each X540-T2 can use up to 17W when both ports are in 10gbps mode

. Even when not doing anything ??? Holy ****.
If you can live with a 1U appliance that has no PCIe slots and limited room for disks, then there are options. I have some with a Xeon D-2187NT, 2 x Intel X710, 4 x Intel X722, 6 x Intel I350 (just 1GbE), and 2 x M.2 slots for example.
What's the Part Number for those ?
Better question is, why don't you just use a PCIe NIC?
Right now I am using the X10SLM-F/X10SLL-F for one Virtualized (Proxmox VE) OPNsense Router, the X11SSL-F for the other Virtualized (Proxmox VE) OPNSense Router

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In Terms of NIC, the Intel X710-DA2 seems to be the best. The Intel XXV710-DA2 is another Option.
The Mellanox ConnectX-4 LX ONLY if in PCH connected Slot (NOT CPU connected PCIe Slot) for ASPM to work correctly, otherwise no

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I was just wondering if it was worth to grab one of these from the US since I am already ordering some stuff from there shipped to Europe via Jetcarrier, so they could come along as well

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But I could also grab some X710-DA2, XXV710-DA2 or Mellanox ConnectX-4 LX if I really wanted, like I have been doing for some other Builds (X10SLL-F, X11SSL-F, Fujitsu TX1320 M3, etc).
I prefer SFP+ since the Switches are so much cheaper (and less Power hungry) though.