An old NIC Supermicro AOC-SG-i2 with intel 82575EB chipset PCIE x1 or 4?

TrueNAS General
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Haven’t checked forum for sometime, just realized freenas now has a new truenas forum :joy:

Anyway, so I’m trying to move some parts around, found this old Supermicro AOC-SG-i2 card. From online search it’s based on the Intel 82575EB chipset, which apparently uses PCIE 2.0 x1 lane.
However, the supermicro manual and web page says PCIE 2.0 x4. The card is x4 and looks like all 4 lanes populated/connected.

From the bandwidth point of view, a PCIE 2.0 x1 (5Gb/s) should have enough throughput for 2x GbE; even PCIE 1.0 x1 (2.5Gb/s) should do the job okay.
Anyone tried this card in a logically x1 slot?

It’s an old card probably not worth talking; but am waiting for a new machine to arrive that needs an additional port, and has a PCIE 3.0 x1 slot available…So just wanna check if anyone tried this before, or should I better order a new card ahead of time :melting_face:

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These things are sometimes kinda weird, there have been similar confusing situations with HBAs.

Regardless, the beauty of PCIe is that it should just work - and as you say, the bandwidth should be fine (best guess, the 82575EB is cut down from the 4-port NIC controller, which would have needed the extra bandwidth in PCIe 1.x systems, so they just kept the PCIe interface to avoid having to redesign that part of the IC).

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Noted, likely just reusing the old or sharing the same design of a higher tier x4 lanes board. Hopefully not some bizarre software limitation that requires x4 to boot :sweat_smile:
Thanks for the quick tips anyway