Why does my minecraft keep crashing? - 1

I have 4 mods installed, Tropicraft, Traincraft, Twilight Forest, and Build Craft, and it crashes every 5-20 minutes and I can't figure out why. I did some research and I couldn't find compatibility charts for all of them but I found one for tropicraft and all of these mods work with that one, so I figured they are similar and should work together. I don't have a texture pack on, and I have the graphics on fast. The render distance is set to normal, and most of the higher end graphics options are off. I thought maybe it was the memory so I boosted my minecrafts memory to 3 GB and it uses around 25 percent of that on average, I get between 100 and 120 FPS, so nothing appears to be wrong. But every once in a while unpredictably it will crash, I won't get an error message it will just say java has stopped working and then it will exit me out, what is wrong? Its really annoying me.

Added (1). And its not an issue with my computer, at least it shouldn't be because my computer can handle almost any game on ultra graphics, I have 8 GB of Ram, and my processor is as good as they get.

Added (2). And its not an issue with my computer, at least it shouldn't be because my computer can handle almost any game on ultra graphics, I have 8 GB of Ram, and my processor is as good as they get.

Do you has the newest launcher and version of mod and mod loader? And if so delete dem modz!

Have you tried updating your Java? And are you using the right version of Java for your computer? I mean 32 bit or 64 bit Java. Try to uninstall Minecraft if Java isn't your problem.

If none of that seems to help try to download a Minecraft launcher and use a mod pack found there. I prefer the Technic Launcher.