I have a Toshiba satellite C660-11k that wont power up. the external power light shows and when I hit the start button the laptop light comes on for a minute then goes off. No fans are heard no optical drive STARTS up. I have bought a new battery, tried installing from disc, and removed optical drive in case that was fouling the start up. I have come to the conclusion it may be a motherboard issue. I have fixed my own laptops with several software and hardware faults but never done a motherboard and with the cost of a new one it may be worth scrapping and buying another laptop. I would be very happy for other ideas or CONFIRMATION of my conclusion. Thanks in a advance If you are able to take your laptop apart, take out the motherboard (mobo). Place it on a clean and dry table (As a  precaution, keep a newspaper with at least 2-3 folds between table and mobo)

1) Connect the charger / ADAPTER to the mobo and try powering on. You may need to only connect part of or the whole panel of the laptop which contains power button. (if power button is not soldered on the mobo). If still same problem, try next.
2) Take out RAM modules, clean the socket of the RAM with a clean / un used paint BRUSH. Clean firmly, never apply too much or any pressure. NEVER USE CLOTH to clean mobo or nearby components. If you have two RAM modules, try with one by one.
3) Re-seat CMOS battery.
4) When you turn on the motherboard,  keep your one finger (dry) on the heatsink / CPU and check if you feel heat.
5) check fans
6) Re-seat processor.

Post back results.Thank you. I shall wait until I build up my courage and the house is empty and then try what you suggest and let you know. I have never taken the laptop apart quite that far before lol. It may be a short while before I come back with results once I have had the CHANCE to do the job. Mind you I have little to lose because without trying what you suggest the thing dosnt work anyway !!