It's funny because this computer runs Minecraft pretty well; way better than my sh**** little Acer, but this error is always popping up. To bad a game developer that actually has some experience didn't make Minecraft.....

To be perfectly honest you need a new computer. Even with 4GB of RAM, your processor and 32 bit OS would probably still lag the game.

xtra RAM, and also try deleting junk screenshots

So I just need more RAM and that should solve the problem?

not to brag but my laptop owns it dominates my LITTLE laptop with used to be cruddy shet i finally found a way to get it to never lag on minecraft NEVER i 1. changed to 64 bit 2. i go cc cleaner 3. i bought the right laptop

You only have 1GB RAM, thats not enough. You need at least 1GB for minecraft and then another GB for your OS.

If you had a 64-bit OS you could use 64-bit java to help a bit.

ur computer isnt the greatest.... it happens to my friend too. its cuz his computer suks ballz. but if ur using hd texture packs and that is happening that is the problem.

Here are the specs


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System Information
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Time of this report: 9/26/2011, 21:07:41
Machine name: D96SFCB1
Operating System: Windows XP Professional (5.1, Build 2600) Service Pack 3 (2600.xpsp_sp3_gdr.091208-2036)
Language: English (Regional Setting: English)
System Manufacturer: Dell Inc.
System Model: MP061
BIOS: Phoenix ROM BIOS PLUS Version 1.10 A02
Processor: Genuine Intel(R) CPU T2250 @ 1.73GHz (2 CPUs)
Memory: 1022MB RAM
Page File: 553MB used, 1907MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 9.0c (4.09.0000.0904)
DX Setup Parameters: Not found
DxDiag Version: 5.03.2600.5512 32bit Unicode

I think that means your Minecraft is out of memory. LOLJK, I don't know, it has happened to me too.

How much RAM do you have allocated to minecraft? How much RAM does your system have?