Can I replace my old graphic card with a newer one? (Same model) (Laptop)

[landskyjj]

I've got a Lenovo Y50
Specs :
Intel I7-4720HQ
Intel(R) HD Graphics 4600
Nvidia GTX860m
Ram 8 GB

I've been using my laptop for about 3 years now, but recently it froze whenever I open too many programs (playing CS:Go and using Chrome), I had to force shut down my laptop for a few times.
Yesterday, it froze again (I was playing CS:GO and using Chrome) so I forced shut down the laptop and when I turned it on again and tried to play CS:GO, the game crashed after 5 minutes play, I figured that my Nvidia graphics card must've been overheat and my laptop must've been using the Intel graphic card hence the crash, I also noticed that the Nvidia graphic card is gone from device manager
https/drive.google.com/file/d/1j4xEZxiogImcymQDGDBahtFEAjLhZ0PP/view?usp=sharing
After finding that out, I tried to install Nvidia graphic card driver and it said "No compatible devices found", so I came to a conclusion that my Nvidia graphic card is broken.

I'd like to add one more thing. Originally, my laptop comes with Nvidia GTX960m but there was a problem so I sent it to Lenovo's outsource repair service, when I got it back, I got Nvidia GTX860m instead, I was angry and confused but it can play games just fine so I didn't complain much

So my questions are

Is my Nvidia graphic card gone for good from being overheat?
(Since it disappeared from device manager)

Can I buy a new Nvidia GTX960m graphic card and put it in my laptop?

 

[hang-the-9]

If they were able to replace the video card, means it is in a removable socket, so you should be able to put in a 960m.