I have a computer with 6gb of ram and Intel HD 4000 graphics. Whenever I play Minecraft, after a couple of minutes of playing some blocks will start flickering. Then a couple of minutes after that everything disappears except for other players, monsters and animals. When I try and force load the blocks nothing happens and all the blocks are still invisible. I've looked all over the internet for fixes to this problem but no of them are mine. Also, I'm not sure if this is related but when I turn on VBO's the game crashes.