How to debug PCI issues?

Ben Greear (
Thu, 27 Sep 2001 18:18:50 -0700

I'm working with a TYAN Tomcat board (i815, Ghz CPU). It's in a 1U
machine with a butterfly riser so that I get two riser connections to
one PCI slot. When I put Intel EEPRO nics in each slot, I can pass
30Mbps of traffic on each NIC without dropping a single packet
(In two days of running).

If I run 20Mbps on one of the DLINK ports, I'm fine, but if I run 10Mbps
on two of the DLINK ports, I start seeing dropped packets on every
interface, and port errors like RX-FIFO.

So, I'm thinking that the DLINK NIC must be screwing up the PCI
bus somehow when more than one of it's interfaces is passing any
significant traffic. I have been able to run 10Mbps on all 8 ports
of two DLINKs on an Intel EEA2 (i815) board, so I suspect the MB.

Does anyone have any ideas how to go about trouble-shooting this


Ben Greear <>          <>
President of Candela Technologies Inc
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