BSOD white snow dots, reboot

So using a alienware laptop and have not installed anything new on it in months only used it to play shantae like 2 weeks back and watched adventure time cartoon like yesterday.

now most of the time i leave it on or on standby. so yesterday i let it powered on to download the mmo scarlet blade.

only to come back today with an error that it had rebooted. I thought no big deal and i left it on and was watching some tv (laptop next to it) and after like 2-3 hours I noticed strange white snow over the screen very tiny dots. then it restarted. when i checked the maintenance it said it was a blue screen. So now Im here. I have had blue screens in the past on other pcs but only when i was messing with stuff so no idea what could couse this.....