I recently after researching various wireless cards decided to buy and install the Buffalo WLI-CB-G54s....
I thought I had found the right wireless card that would work with my Ubuntu Fiesty 7.0 version and Windows xp...

Now it seems that this card has some sort of problem that it crashes Ubuntu ... freezes it completely can't even shut it down properly only via on/off button... this is the same with WinXP...

Now... Anyone has a solution for this...? HELP!!!

either I need to remove this driver and re-install it or I will need to give up this futile card....

HELP!!!!!!!!!!!

If it is crashing both OSes, that is a likely a hardware problem. I'd return it to wherever you bought it and ask for an exchange or a refund.