Cant see Point light and i see black things which shouldn't be there?

Guys help plz i dont know what to do, this is a very strange error i guess? i got this right when i installed it and first opened, please help.

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What is your video card, some times it happens to me in some new games, but it doesn't happen to my other computer, in other words, it is my video card and this error can be because of yours.