Random System Lock

[BerserkHealer]

I've started having a problem when gaming where my system will just lock up, the mouse still moves and i can hear music playing and people talking in discord but they can't hear me. I have to do a full system reboot by pressing reset button as i can't get anything to work on the system. I have seen and heard things online about a windows update that's been messing thing up im just wanting to make sure it could be this and not anything else. I have started OCing the GPU but tbh it did do it a few times before i started to OC. my OC is dailed down as well its only 90 on core and 350 hz on memory as it crashes out on about 120 and 600. so my clocks stay about 2050 hz. on saturday i gamed all day and had it OC and it didnt crash once and then the day after it crashed. it does it on other games as well. kinda makes me think it might be gpu related or OS 

 

any ideas?