We have a server with an Intel S5520HC motherboard, two E5620 processors, 6x2GB memory modules and four 1TB hard drives in RAID 10 connected directly to the board. I'm trying to be as detailed as possible in case any of this connects.
When it was purchased (before I got there), it had a PCI (consumer grade!) gigabit Ethernet card installed, and when this failed, my testing of the onboard NICs revealed that they didn't work. At all. It had PCI identifier 8086:10AA which has been discussed at length previously.
Armed with this knowledge, I picked up an Intel PRO/1000 PT quad-port adapter and installed it into this system. Imagine my disdain when it didn't even appear! For science, I installed a PRO/1000 CT desktop adapter, which worked.
Ok, says I, I've got an R/S quad-port NIC. Before I called the vendor to rant and rave at them, I decided to science some more. I installed the card into a Dell PowerEdge 1950 I had lying around, expecting to see the same behaviour. Nope - the card worked perfectly, even in the pre-install environment of a Windows Server 2008 R2 install CD.
So what's going on here? Sure, I could put the lack of action on the on-board NICs down to dodgy EEPROMs (as stated in the links above), but why would it also affect an enterprise-grade quad-port card?