Upgraded cpu not working

Hi guys,

I tried to upgrade my old laptops cpu from i5 to i7 740qm as the i5 one was not fully compatible with the motherboard.

Anyways I replace the cpu, everything is connected and placed in the correct place. and i try to power up the laptop and all the
LED lights and the fans switch on for 2 seconds and switch off, and the laptop tries to restart itself in another 2 seconds and the same thing goes on and on until i pull out the plug or the battery. I am not sure whats wrong or if the cpu is faulty so I switched quickly back to the i5 proccessor hoping one of you knows whats wrong, so help please?