You have figured it out and all that you need to do is ask the maker to fix your laptop.
Lately im trying really hard to find the source of my problem.
I got a Packard Bell laptop i5 2410 / 540gt.The laptop was running apps and games really good without any problem .
One day i played diablo 3 in a 4 players group and at the momment i teleported to the battle zone , my laptop freezed for about 15 secs then started to lag very bad ( lag in game no lattency like ping ).Since then in every game my laptop lags a bit , little frames for some milisecs every time i explore new contnent , when new things are around or new spells are casted .Some times its stuck for 3, 4 secs when u change ur zone instant ( its like he loads next images with delay )
i restored all system , tested all posibile configurations from nvidia control panel , disabled all battery saving stuff , tryed numerous drivers for both intel6 chipset and geforce 540m , even unpdated to my latest bios..nothing worked
The tempretures are good cpu in 50-57C in clean windows , increase for up to 85 in heavy gaming , temps that i know are ok
HDD wont pass 44 C / no erros all clean
Ram seems like working 100 %
GPU dont pass 70 C with high details on game like D3 or in graphic software.
The only thing i dont know how to test its the MB
As far as i know similar issues have been spoted on some Acer laptops also.
I would really apreciate every info and help.