My home computer (and my wife's) are working fine connected to a Netgear FVS318 router that gets connectivity through a Zoom ADSL modem. I've swapped cables and router ports between the work computer and our two home machines so that's not the problem either. Installed a PCI NIC and tried it with onboard LAN disabled and enabled- the behaviour is the same with either type of adapter. Initially I tried resetting the winsock and doing a repair installation of XP pro (twice)- no connectivity with or without a bridge. Did a formatt and clean install (twice), no better. Ran 8 paases of Dban and installed windows 2000- that was when the bridge started working so I reformatted and reinstalled XP pro and the bridge has continued to work.
Since the Foxconn 661M03 mobo has onboard 1394, I tried removing the creative audigy platinum EX soundcard in case its' integrated 1394 adapter had suddenly decided to create problems- no joy there either.
When the connection first dropped, I had no hardware address for the onboard LAN adapter and didn't get recognition until after running Dban. Interesting how there was no hardware address for either card until that drive was truly wiped. Tried switching out the two 512mb RAM sticks just in case (no other symptoms of bad RAM). Flashed the BIOS- no improvement but now I've got a nice "pentium 4" logo that displays when I boot. With the sound card out there's only one 1394 adapter to include in the bridge but, without at least that one 1394 adapter in the mix, neither lan adapter will recieve any packets.
It seems like there must be some kind of hardware problem within the motherboard with MAC resolution but I just don't know enough about how TCP/IP is proccessed at the basic hardware level to be certain. This computer has been rock-steady for two years and even though it seems to function ok with the network bridge installed, I don't want to put the machine back into everyday service with a potential reliability issue and I wouldn't want to swap out the mobo if that's not the answer. Anybody got any ideas?