I'm looking to mount my TV to the wall this weekend (in my front room) and having a knock on the wall parts of it seem hallow, which would likely indicate that the plasterboard is mounted a wooden timber support behind it (most likely has a proper name). I'm looking to mount 2 of the bolts to this wooden frame and the rest to the plaster board. However, i need to know how wide the wooden timber is likely to be behind it (i want to try and place it into the center of this). My plan is to locate the studs on the plasterboard using a strong magnet. I assume there will be 2 studs for each end of the plasterboard's that connect to it.