Unrestricted performance with bigger psu?

my laptop comes with 90w charger. i have i5 2430m and 6630m ati. if i get a 135w charger (over kill i know) doesnt it allow more power to the system thus no throttling. and say if i overclocked it or even got an i7 upgrade to 2620m/2640m. would these thigns make it worth while to help prevent overheating and throttling and better performance?

Also Thinking alot about doing and upgrade. i had an engineer come to my house to replace heatsink as i paid for onsite warranty as ive heard stories about some laptops not coming back in same state it went. and all he did was unscrew it and apply some thermal paste which was better than stock. he didnt know the name of it. but it helped my laptops lagging gpu performance back up again.
and example how bad my gpu was in wei scores. graphics scored a 3,0 and gaming graphics got a 5.2. and tested this lots of times. But my laptop was doing alot of over heating and cutting off. now its back up to 6.7 for both. my cpu is still abit high. but i may change this because how they gonna know if i changed the cpu right when my warranty is onsite and i can change it back if anything happens? so will an uprade also be worth it?