ASUS V550ca Power / Graphics issue

[jamidodger1]

I've got an Asus V550ca that's always been a little strange since purchasing it, it's always had power related issues ranging from not shutting down (hanging on black screen) and random power offs for no reason when in use.

Cut to last week, swapped out my ssd with a hdd and went to power on, black screen and no backlight. Thought was strange so reseated ram, left off for a bit and tried again no luck. Since I've swapped out every replaceable item, reconnected all connectors, even going as far to re-applying thermal paste to both cpu and integrated graphics gpu with no luck. (note, when looking at the integrated graphics chip it was slightly discoloured - lighter green in some areas, not sure if it's related). When powering up you can hear the hdd and see/hear the fan powers up although no signs of life including caps lock, num lock don't work or respond. If you remove the ram and turn on it keeps the numlock light on but continues to do nothing. 

Think that the graphics chip is dead but didn't know if anyone had any ideas to try before it gets stripped down and disposed of.

Thanks
Jamie