My Mac: 800Mhz Quicksilver, 1Gb RAM (factory fitted), OS X 10.4.3 I've never had a problem with OS X so far as crashing before, just the odd application quitting, MUCH BETTER than OS 9 on my old G3 was! These are the problems I keep getting when the connection becomes unstable: Loses internet connection, cannot launch applications (just bounce in the dock forever), can't quit internet applications (safari, limewire), have to restart then need to remove USB WLAN adapter and plug it in again! ...As above but can't even restart, need to use button on front of case! Total system freeze, shows standard multi-lingual "You're Macs' not very happy" alert box over a frozen desktop, have to restart with button on front of case! I've got the most recent drivers for the USB WLAN, I wasn't going to spend nearly £100 on a 4 year old Airport card off eBay so it seemed the most sensible option. Anyone suggest anything to sort this out, maybe a system update of some kind? I find it ridiculous that the same USB adapter works fine on a neighbours PC and when it loses the connection, it doesn't crash XP! OS X doesn't seem to be any more stable than OS 9 in this respect because if losing an internet connection through a 3rd party device makes the whole system go belly up, it's hardly the best advert for apple given my neighbour is keen to move to the platform when he gets his next laptop!