I had a gigabit ethernet switch connected to a wrt54g wireless router connected to an apple airport connected to a cable modem, in that order. There was a lightning storm and, I don't remember which, but it came through either the cable or the power. At any rate, it fried about half of the gigabit ethernet switch including the uplink port, so I had to replace it. It seems to have damaged the downlink, to the switch port of the wrt54g, but NOT the uplink to the apple airport ?!?

A while ago I had a cable modem and an ethernet card fried by lightning. The card still appeared for the computer (this was a windows2000 machine I think) but no connection.

But here I'm wondering how much slower my connection likely is on the wireless router because of the damage. Any suggestions? I could write a throughput tool I guess and plug the uplink into another computer, but is this a common thing? I.e., that an electrical appliance is damaged but not broken?

PS: I say "wireless router" a lot, but that's just the model, I'm only using it as wired.

Are you sure that is caused by lightning storm ?
Even if it was a indirect hit the damage will be much more than you describe.
Well one point is that I do not know in you're country the power supply and telephone line is under ground or not.
Here every thing in under ground and still the advice is during a lightning storm unplug it from the power socket and take areal out
And if it is indirect hit so it hit something nearby a areal or something like that the damage is great

Since you have seen this more than once, you really should invest in a UPS. Even if you only get one large enough to keep your system up (with everything plugged in) for a couple of minutes it will protect everything that is plugged into it. Since you have cable internet make sure to get one that protects cable throughput too. Odd power can lead to early failure of electronic equipment and cause lots of strange (often unrepeatable) behavior in computers and other electronics.

A direct his probably equates to vapour deposition of your hardware on nearby objects. Sorry, I just couldn't help myself there. An indirect strike, will cause a significant voltage gradient outwards from the point of the strike hitting the earth. The field around this voltage gradient cuts through cables and induces huge currents in them. It is usually the voltage associated with these currents that do the damage, quite a distance from the point of the strike. It's why cattle should learn to stand on one hoof during lightning storms, because the gradient between any two legs can be in the order of several thousand volts, not good through either the heart or the testicles. Guaranteed to make the eyes light up - briefly. Zenner barriers seem to be a form of protection to protect equipment where the network outside a building is likely to suffer this form of disruption. No point in importing large voltages on lines between remote sites.

Well this storm snuck up pretty fast, and, being that my house didn't light on fire, I'm guessing it wasn't a direct hit.

I used to have a nice UPS but I was moving around a lot and I think some ex girlfriend I had to stay with has it now. I don't have the money to buy a new one. There are two or three surge protectors (decently expensive), with ethernet jacks at different points on the line. This blew through those apparently.

I think it hit the transformer outside, its above ground everything. I was there at the time, it snuck up very fast and it was the loudest crack I've ever heard, very bright.

But really, I'm wondering if anyone is, just in general, in the know about computer equipment functioning after any kind of surge damage, not necessarily lightning. Does it usually stop, does it work at 1/3 capacity? Is it intermittent? I mean I assume there's different cases. I think the gigabyte switch blew out because its circuit board had certain components too close together and the surge jumped something, shorted it, so only a few ports ended up working. But the routers a little weirder. Not sure why it would still basically work... just wondering, I doubt there's any stats on this kind of thing.