Question Asus g551jm gpu help!

Aug 2, 2020
Hey everyone! Hopefully this post is finding itself in the right place, never been on here before so apologies of not!
I recently replaced the keyboard on this laptop as the cable for the led had broken, everything was running great for a while then during a restart the fan started going full noise and in device management I noticed the video card had disappeared.. it's a gtx 860m on board.. also the nvidia software didnt notice the hardware either... anyway I rolled with the Intel HD graphics for a few hours but couldn't associate it with a software fault and even tried to control the fans just so it was more bearable to no avail.. left it a couple of days rebooted and the fan was quiet, graphics card recognized and everything was great again... then alas! Today same issue.. fan on and no nvidia card showing up...

So.. can anyone help, I'm very new to this so I'm assuming something is loose although I dont know where to start ! Any pointers would be hugely appreciated ..