Hi there. I've just had exactly the problem you describe on the Advent 5480 laptop. Blue screen of death followed bu update bios, go to hardware-updates.com which did look dodge. So I got the bios for the advent from http://members.driverguide.com/driver/detail.php?driverid=121672. You have to join, but it's no hassle and free. It seems to work. I've rebooted three times with no blue screen. Make sure you chack the number on the bottom of your laptop to ensure it matches. And I suppose I should say this is all at your own risk. There's warnings all over the driver site. As I said for me it seems so far so good.
Hope that helps.
Richard