White screen in middle of game.

I had this issue a couple times before the update and before i started using mods, so I dont think either of those are the issue. What the issue is, is that in the middle of game play all of a sudden the whole screen will go white. I can hear my sims but can not see anything but a white screen. I have left it like that, hoping that it may correct itself, but no, and the only way to get out of it is to "alt, ctrl, delete" and force it to end it. And when I go back in, Im right back to where I started. I had just been making sure I saved it every so often, in case it does do that, but this time I didnt and I did alot of sim living and lost it all! So decided it was time to investigate the issue. 

Thanks in advance for any help