samsung ps42b451b2w

[samisat]

Hi flaks I got in this tv which no pic but got sound. as normal I checked ysus and driver for faulty fet or caps but nothings found so I put bake the Ysus and driver on tv and back light fired up. tv worked for 3 days and then one morning same issue,I did unplug same board and put them back then again fried up everything ok but after 2day went same issue. any idea?
Thanks for ur help