количеством выделенной оперативки проблему не решить. тем более на 32 битах больше гига не даш, сколько не напиши. а вот кстати пара строчек из краш репорта
---- Minecraft Crash Report ----
// Surprise! Haha. Well, this is awkward.
Time: 11.05.16 23:46
Description: Registering texture
java.lang.OutOfMemoryError: Java heap space
at net.minecraft.client.renderer.texture.TextureUtil.func_110993_a(SourceFile:289)
at net.minecraft.client.renderer.texture.TextureUtil.func_110995_a(SourceFile:279)
at net.minecraft.client.renderer.texture.TextureUtil.func_110989_a(SourceFile:209)
at net.minecraft.client.renderer.texture.SimpleTexture.func_110551_a(SourceFile:48)
at net.minecraft.client.renderer.texture.TextureManager.func_110579_a(SourceFile:72)
at net.minecraft.client.renderer.texture.TextureManager.func_110577_a(SourceFile:40)
at net.minecraft.client.gui.FontRenderer.bindTexture(FontRenderer.java:854)
at net.minecraft.client.gui.FontRenderer.<init>(FontRenderer.java:57)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:491)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:881)
at net.minecraft.client.main.Main.main(SourceFile:148)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)