Hello guys, So I have a Lenovo y50-70 and I'm fixing it for a friend. The laptop had windows 8.1 on it and and was able to format it into new OS. The laptop does not read the hdd sometimes and won't let me boot from the hdd. It works only once every 15 times, if I keep restarting the laptop. However, it still read it on the bios. I tried to change the settings on the bios such is AHCI to compatible, but still not luck to get it working currently. Any suggestion maybe? Thank you for your help in advance.