I have this asus n3700-a/k20ce model and there is no jumper to clear cmos. Pressing alt+r wont work. I have taken the battery out for more than 24hours even tried up to 2 days. Shorted the negative and positive of the battery. Even stripping all the cables out but no luck at all. This is frustrating. Even asus couldnt give a good solution. Maybe next time before u buy an asus mobo.. better check whether it havr a cmos reset function or not.