Sounds like some hardware component has to be replaced, like the CPU or the motherboard. This might cost more than the laptop is worth. Ask a repair shop for an estimate.
Kees
The laptop is Sony Vaio VPCF22J1E/B,with Intel core i5 2410M 2,3ghz processor, NVIDIA GeForce GT 540M gpu, and windows 7 home premium.
It has had overheating issues for a while now.Sometimes it would shutdown randomly while I was gaming.twice the screen froze while gaming and would not unfreeze ( I waited for 15 minutes).( it may have been the whole laptop freezing,because I think the keyboard was unresponsive too)
Two days ago it shut down randomly and when I tried to open it I could hear the fan and saw the start button light up for about 3 seconds and then they stopped.I've been trying since then,but no change.The fan starts, the button lights up,and after 3 seconds they stop.The screen shows nothing,the keyboard doesn't light up.
This has happened several times in the past but after 6-9 tries it would power up.
-with the power cord connected and the battery in the button that lights up when the battery is charging is lit.
-It doesn't even enter bios
After googling:
-I've tried removing the battery and power cord,pressing the button for ten seconds and then connecting the power cord to start it up.
- I've tried with only the battery ( it is fully charged)
- I tried with a disconnected hard drive, ram,network card,camera, cd-dvd drive ( all the combinations I could think of)
- I connected my hard drive in another pc and it was ok
- I changed thermal paste and cleared the fan
Still nothing.
Sorry for the bad English.

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