to check if it is the inverter
shine a torch on to it from close quaters and u should see something on the screen
good advice, basically an lcd is backlit, i.e. light is shone through it, much like a the negative of a photo, or photographic slide.
start it up, give it a few mins and then shine a really bright light onto it, if you can see a faint picture, i.e. desktop / windows loading / logon sreen, its back light or inverter., if nothing, it could be something stupid like the lcd panels connectors have come dislodged from mainboard, so wip keyboard out and check those, then also check inverter leads on boath mainboard and panel.
another one to check is the hinges, ive had quite a few laptops whereby the hinges have become damaged and have then damaged the ribbons for the lcd, so check around there.
mainboard replacement is not a root i would go down myself, i a repair laptops almost daily / weekly, too many variables unless you get your replacement from a reputable dealer, second hand boards, too much can go wrong, plus the prices of them are extortionate, and then you have to strip laptop down and reassemble before you even know its working (within reason).
bristolcomputerrepairs
have yo tried another hard drive in the machine? whats the exact symptoms, with the hard drive in, does it start up, at what point through the POST does it get? it could be a seriously damaged hard drive which is preventing it from even POSTing.
need more info!