Trouble with PCIe x1 Slot in OptiPlex 390 SFF with i5 2400
Hi, according to the specs, the only difference between the x1 and x16 PCIe slots in the OptiPlex 390 SFF should be max wattage (max 10W vs 25W) and the two cards I try to install should not exceed that. They are
- 2-port USB 3.0 expansion card PCIe x1 with Via VL805 Chip, or - 2-port SATA expansion card PCIe x1 with ASM1061 Chip
However, either card only works (more or less seamlessly) when installed in the x16 slot. I want to install one or the other. Furthermore, when I install them in the x1 slot, the onboard NIC (Realtek 8111) goes inactive during boot. Procedures were observers with Debian 11 but also confirmed with Win 10, both as 64bit. Tested on two identical machines. BIOS is A14.
Since the x16 is already occupied by a PCIe-to-Nvme adapter card that requires minimum x4, keeping the cards in the x16 is no option. Also, of course, I need the network connection.
Any ideas what the root cause is and how I could fix it? Thanks!
PS: I remember observing a similar behavior on a T110 server. There, the x1 slot also only accepted the network card that we bought with the server itself (read: from Dell) but no other extension card. Maybe these x1 slots are somewhat limited and do not fully comply with PCIe Gen 2 standards?