I recently installed Minecraft 1.7.2 on my Ubuntu 12.04 64-bit with all the correct Java packages and LWJGL, but when I go to play it, the FPS rate drops to ~3 fps and freezes every second, making play almost impossible.
Specs:
RAM: 3.6 GiB
CPU: AMD Athlon(tm) II X2 245 Processor × 2, 2900 MHz
GPU: GeForce 7025 / nForce 630a/integrated/SSE2
Disk: 242.2 GB
Java: 1.6.0_31
OpenJDK Runtime Environment (IcedTea6 1.13.3) (6b31-1.13.3-1ubuntu1~0.12.04.2)
OpenJDK 64-Bit Server VM (build 23.25-b01, mixed mode)