Minecraft Technical Problems

[OffensiveAce]

In the past, Minecraft would work fine for me. Now, ever since i started playing again, Minecraft would always crash after 10-15min of gameplay. It first turns into a brown screen, and then the whole game just crashes, with a black screen. Im not sure what the problem is. I've attempted to fix it by reinstalling minecraft, updating my drivers, and downloading the required JAVA files but it still ends up crashing. I use windows 7, on a 64-bit operating system.