Hi, I have a Power Mac which has lost the use of its inbuilt network port -its old and I suspect some kind of electrical fault. Since I want to use Wifi anyway to upgrade it from 10.6.8 (Snow Leopard) I have borrowed a Tenda usb wifi dongle. This has drivers etc for Snow Leopard on its web site and as far as I can tell it works. I can connect to my router and see all the wifi networks available. However the mac is locking up whenever I try and access the internet, Apple store or software update. I don't get a beach ball, but the only thing that I can do is move the mouse pointer. I cannot run any apps after trying to connect to the .net. Everything is OK if I don't try to connect to the .net. When I look at system prefs - network it shows the dud network board is connected, but it is not as its unplugged. Could this be causing the lock ups? How can I test/fix? - I'm not bad with the command line but would prefer not to have to use it if possible. Hope someone can help.