First, Sorry for the silly question. I have ASUS K42F VX308D Laptop. It has cooling vent (with Fan) on left side and some vents openings on the bottom. One for CPU, one for memory devices, one for motherboard, and other one is for HDD. Now, when i use it on my bed, i used to put it on hard covered book so that left side cooling vents are open to exhaust air. But the book covered one of the vents located bottom of the laptop. Is it necessary to remain open all the vents at the bottom of it? If i constantly do the same thing, will it face an overheating issues?