You'll want to see if samsungparts.com has a service manual. So far, your normal Samsung contacts are for user serviceable items. You seem to be a TV repair person and you'll want the service manual to see what the diagnostic flow chart tells you what to change next.
mine does not even light up ( the power indicator LED) no clicking noise , nothing, it was working and then suddenly stopped and nothing happens, i have changed the fuse, tried different power lead, capacitors look fine, cant tell wether the T6.3H fuse has gone but i have ordered a replacement anyway , what is going on? will a new power board sort this? i can get one but ide rather not have to fork out £39.99 for a replacement, and if i was to get one would it definately fix it? i have contacted samsung support but yet to recieve a reply