Lafiel on 22 November 2009
the best way to avoid YLOD is to have the PS3 horizontal and to exchange the thermal paste with a high quality one after the warranty is gone
YLOD is caused by an overheating of the chips and the board, which happens because the thermal paste Sony used sadly is able to slowly flow from the chips if it's warm (it's not viscous enough), so after time the cooling won't work as well anymore and if the chips don't deactivate themselves fast enough they or the board will overheat and be damaged -> YLOD
