Identifying whether a pci device is x1, x4, x8 or x16

[Bjørn Mork]

Kevin Wilson <wkevils at gmail.com> writes:

> Hi all,
> Is there a way to find out whether a PCI device in a given Linux
> machine is x1, x4, x8 or x16, in terms
> of physical dimensions (without opening the box...)

Sure.  Use something like "lspci -vvvnn" and check out LnkCap and LnkSta
under Capabilities.  There you can see both the number of channels and
symbol rate.

For example for an x8 card in an x4 slot (connection-wise - the
connector is of course wider or the x8 card wouldn't fit):

LnkCap: Port #0, Speed 5GT/s, Width x8, ASPM L0s, Exit Latency L0s <512ns, L1 <4us
LnkSta: Speed 2.5GT/s, Width x4, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-


Bjørn