I'm maybe a little late for this, but I did find a solution for this frequent trouble with this Laptop.
First, unplug the GFX card, and try to power on the computer. If it does'nt, then it's probably not the GFX card. Try next step. If it does power on, then best change the GFX card for a new one. You may try the heat gun tip, or baking, but these do not last very long. Prefer graphic cards that don't over-heat too much.
Second, remove the CPU. If it starts, then it's the CPU which is faulty, and you better change it for a new (worth 20$ at max.). If not, then it's something else (motherbaord, power supply circuit, memory modules).
Third, try the same thing with memory modules.
Hope this can help
P.S. : sorry for my english, but I'm french