Question : Problem: how to strip a sony viao pcg-k315s notebook

need to clean the cpu fan on sony viao notebook (pcg-k315s). How do I access the fan

Answer : Problem: how to strip a sony viao pcg-k315s notebook

Your specific laptop is not listed here http://repair4laptop.org/disassembly_sony.html, but I think Sony laptops have enough commonality that it would be similar.  Most of the time, it's just a matter of removing the bottom screws and taking the cover off.  Some manufacturers hide screw holes under a label or rubber pad.  The fan will be located near a vent on the side.  Be sure to keep track of where the screws came from, so you can replace them.