Any way to track how many hours an lcd has been used?

like to know if there is any way to tell how many hours an lcd particularly a samsung lea656 has been used. Ive recently purchased a store model at a discounted price and have been told by the store manager that they alter the display sets every couple weeks or so. Im not too worried considering the price i paid plus the life span of these tv's however its just something i would like to know for my own dis/pleasure. hehe

bump

if only for a yes or no

bump for more insight into this matter

the tv set in question is the samsung a656 (40 inch euro edition)