Black ground glitch in salem?

[Fishbro2]

Hey guys I had a friend of mine to play salem. He can play but everything looks very messed up to him. http://i.imgur.com/JiuIrLW.jpg
Any idea what is the cause of the problem, but more importantly how to fix it?
If you need extra information on this please let me know as I do believe somebody somewhere had the same problem and found a fix. I just can't find the topic

[staxjax]

He needs to check for video driver updates. If he is using beta drivers, then he should revert to the last official drivers for his GPU.