I have my LAPTOP SONY VIAO PCG-61211W almost 1year stocked and it is not working.

i can turn it on and has the light button, but it suddenly turn off in a second repeatedly. i OPEN the case and i tried to reset the memory, hdd and the processor and placed new thermal paste and cleaned the exhaust fan, while the case is open i tried to turn it on, the fan is working and it synchronized with the light button but again my laptop is repeatedly on and off.

kindly give me a advice to fix  the problem of my laptop. thank you!Usually if only fans spin up and it doesn't turn on, it's a dead motherboard. Any beep codes?there's no beep at all. is there another way to fix the motherboard?Not unless you're a computer ENGINEERING major and know advanced CIRCUITRY and have spare materials.

Best to buy a new motherboard or check your warranty.all i know about motherboard is to reheated the chipset. is that helpful?You can try it if you have no warranty. It may help, it may not. If you have warranty, I definitely WOULD not try it.

There's no easy way to diagnose exact motherboard problems.As has been said above, if it is under a year old it is most LIKELY still under warranty, use this!