I just upgrades my iMac to snow leopard. I did not see this problem right away but about a few weeks later. My computer is really, really slow when I surf the internet. But it is not slow consistently. Sometimes pages will load immediately and other times it will tell me I can't open the page due to the server not being found? I really don't know where to start looking for a problem. Could I have a virus? Could the Airport just be getting old and starting to fail? Do I have too much info on the computer already and that is effecting something? Could it be the Snow Leopard? Could someone hacked into the modem and is jogging the bandwidth? ( I don't have the wifi locked but live in a pretty rural area) Any help or direction would be very helpful!