you guys sure know how to make a new member feel welcome. Man I wish I was as smart as you all. I think I'll find another forum to join since I cant get an answer to a question without a bunch of smart assed comments
Dude, chill for a bit. Only one of us have made a smart@55 comment so don't judge the whole forum on the actions of one man here. Everyone here is welcomed with open. You are free to come and go as you please and no one is stopping you from doing that.
Anyways, time to be serious. From what you decribed, it seems to me that you have either a graphics card issue or maybe it's just a bug since the demo is still a demo. Have you updated you video drivers yet? Have you installed the latest updates for Windows? Make sure you have those.
All in all, you should be fine if all that you experience is just the blackouts.