Vista reboots in safe mode all by itself!!!!!!

I sell prebuilt PC's and laptops for a living (if your aussie, i work for my local JB hifi!!!!!). Occasionly (read: often!!!), people will bring their PC's back to me for tech support rather then call the company that made the PC. I don't mind this as its mostly just end user stuff ups or simple issues i have seen before (or read about here) and fixed. This one issue today was weird coz i neither myself or my colleages had seen this before. It was a 2 month old acer laptop running vista home premium, above entry level specs (ie 2ghz DC, 2gb RAM, etc) in the new chasis with the 15.6'' screens with the D-Pad on the side. The laptop kept returnign to Safe Mode when ever we reset it, even after checking all the right boxes in msconfig. after about 15mins of reseting and clicking and changing settings in Msconfig, it finaly became stable and would return to normal desktop after numerous resesting via the start menu.Just in case this happens in the future or continues to happen to this customer, whatsuggestions do you guys have for easy fixes? have any of you seen this before?thanks guys!!!!!!! Vista reboots in safe mode all by itself!!!!!!
As soon as you turn the laptop on then press F8 then select Normal Mode,,,see if its fixed after that.Vista reboots in safe mode all by itself!!!!!!
the laptop has come back, so fingers crossed, but i'll keep it in mind, thanks!!!