Recently i have started to face this issue on my lenovo y510p, I was using windows 8.1 then, and for the first time my computer get freezed, and the error pop up

Microsoft Windows
The application is not responding. The program may respond again if you wait.

I thought there must be some issue and error will go away, but to my surprise this error start to pop up regularly after using my laptop for 15 - 20 mins, my system get freezed, to get over this issue either i have to wait for next 5 mins until this dialog box will close or i have to shut down my laptop by pressing power key.

Second issue that i start to facing after this is when system restart or start, sometime i used to get this error "UNMOUNTABLE_BOOT_VOLUME", system when restart automatically and after 5-6 try system get started. This error is not persistent it appers sometimes.

When this freezing issue become regular i thought there must be some issue with windows 8.1 so from my end i did following things:

i) Upgraded my laptop to windows 10, issue was still there.
ii) Used lenovo one key recovery and set my laptop to initial position which was windows 8, issue was still there.
iii) Again upgraded to windows 8.1 and windows 10 and issue was there in both again.
iv) Finally i downloaded a windows10 IOS file from official windows website and format all my drive and did a clean install of windows, problem still persists.

Someone please help me regarding this how to solve this issue and what are the possible reasons for this issue ?