Re: My Vaio Y Series can't detect the hard disk on bios screen, showing "operating system not f

Hi Abanlean,

Welcome to Sony Community!

Is the new hard drive detected on BIOS? If it's detected and your getting the error "operating system not found" then you need to install an operating system. If it's not detected, you have make sure that the new hard drive is compatible with the system and that all the connections are properly placed. 

You may visit the link below for additional troubleshooting steps,

https://us.en.kb.sony.com/app/answers/detail/a_id/44854/p/48903,49902,74250,90772/c/65,66/kw/operating%20system%20not%20found

For further assistance regarding your concern, please contact the Sony offices/Sony representative offices nearest to your place of residence in Asia Pacific region http://www.sony-asia.com/countryselector.html?hpid=countryselector:AsiaPacific. Due to proximity, they are in a better position to respond to your questions or concerns.

Regards,
Jen

Answered your question? Glad I could help! Please Click the "Accept as Solution" button below.