Hi, how are you all?
I have bought 3 of this same cards from Aliexpress to use as a peer to peer connection between my PC, my NAS (TrueNAS) and my tests PC with Proxmox, these cards have arrived with the PCI-E 1x part cut down with some saw or similar, so, to me it was a thing less to worry about (I didn't know that will be delivered this way).
After analyzing the boards some more, I've discovered that the thermal condutive material between the chip and the heat spreader was dry and have replaced with some good quality thermal paste, in this process I've discovered that the chip is a Intel X540 AT2 (looked legit to me).
On the powering the card for the first time I've noted that It's get very hot and have added a 4x4cm cooler fan do minimize the heat on the heat spreader, it worked very well.
Have made a 5m Cat6 crossover cable (the PHY on these cards does not invert/convert 568A to/from 568B automatically) and tested some file transfers between my PC and the NAS, the results was pretty good.
Hope these informations are helpful to someone