Hlua (Vanlalhlua or Rohlupuia or .....???

), it could be a driver problem as suggested by ravi. But there are many other things that could cause those symptoms. At the moment, we have too little information to go on with. Sometimes these things have to be narrowed down step by step.
It's possible that we're from the same town. If you'd like to make personal contact, send me a PM with some info about yourself such as your location, etc. I don't want to make my identity public.