Laptop hibernates by itself

[gtm22]

I bought a laptop a year ago, everything worked perfectly but like a month ago started to hibernate by itself; with no prior warning (no error message or sound) it just start hibernating.

Already checked the power options and set everything to never but the problem persist, i send it to 3 different "laptop specialized" services but they told me they cant find the problem,they haven't found any problem with the cpu, gpu, motherboard, ram, hdd, power brick, or overheating issues.

since i bought it second hand the warranty has expired and i really dont want to buy an expensive replacement motherboard.

 

any ideas what could it be

 

the laptop is a hp pavillion dv7-6185us, i7 2630qm, hd 6490m, 6 gb ddr3

 

 

 

sorry for my god-awful english, hope you can understand some of it at least

 

[Tedster]

Welcome to the Forum.

 

You've done everything I would know to do so I'm pretty clueless.

 

Try running some malware/antivirus scans if you haven't already. Try using MalwareBytes, with the free version and scan.