Well, Jeff, you didn't give us much to go on. What version of GNATbox? (2.2, 3.0.1, Lite, Pro, ???) What is your GNATbox? (processor, memory) What kind of NICs and, what settings? What have you done to diagnose the problem? Even the name of the cable service provider could be useful.
However, here are my virtually-no-information tips: 1) dare I say it? I've had *similar* problems to this with 3C509 cards on GB2.1 and 3.0.1. HOWEVER, my results were somewhat different, as when pinging, I got a message about no buffers available (something like that... One of these days, I'll go back to the 3c509s and fully document the problems, but I'm enjoying a very stable GB now). You are apparently sending a ping and getting a response, which I didn't get, so it is likely you have another problem. 2) Defective NIC, possibly thermal. Try swapping your external and internal ports in software (and cables!), see if the problem follows the card. (i.e., when it "breaks" you can ping your external gateway, but not your internal computers). If so, replace the card. 3) Bad cable? I have a bad cable in my system which rears its ugly head every once in a while. I leave it there just to keep me in practice troubleshooting 8-) (actually, I'm too lazy to remake it and too cheap to replace it, but the troubleshooting makes a good story.) It's a long shot, but it is possible. 4) Is there anything else in the computer? i.e., Sound card? Pull it, if there is. I've seen cards go "deaf" like yours when there is an interrupt conflict. Why it would work for a while _then_ die, I can't explain. However, most of what happens with plug and play cards I can't explain. Even if there is nothing else in the box, you might try moving the IRQ of the offending card to something else (on edx series cards, you have to change the I/O address, too). Unless you tell me you have 3c509s in your GB, I'm going for defective card. NICk.
