Server lag in singleplayer

This is mostly due to a broken graphics card. Invalid.

Please force a crash by pressing F3 + C for 10 seconds while in-game and attach the crash report ([minecraft/crash-reports/crash-<DATE>-client.txt|http://hopper.minecraft.net/help/finding-minecraft-data-folder]) here.

I was able to confirm that as soon as I loaded up a world I created in the 14w17a snapshot. Blocks regenerate for a brief second is one of the valid side effects. As for the lag, that is mainly client-side, but would seem server-side as this lag is most often seen on servers with less than 4 GB of RAM (my computer has 2 GB, and it still can't handle the immense amount of lag).

Ram shouldn't matter since Minecraft only lets you use half a gig of ram. Or does the server script let you use more?

---- Minecraft Crash Report ----
// Shall we play a game?

Time: 4/27/14 4:11 PM
Description: Manually triggered debug crash

java.lang.Throwable
	at bja.p(SourceFile:1467)
	at bja.ai(SourceFile:801)
	at bja.f(SourceFile:755)
	at net.minecraft.client.main.Main.main(SourceFile:121)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at bur.a(SourceFile:308)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bww['winner321123'/0, l='MpServer', x=-35.30, y=91.25, z=13.88]]
	Chunk stats: MultiplayerChunkCache: 529, 529
	Level seed: 0
	Level generator: ID 01 - flat, ver 0. Features enabled: false
	Level generator options: 
	Level spawn location: 0.00,61.00,0.00 - World: (0,61,0), Chunk: (at 0,3,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 498426 game time, 6000 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
	Forced entities: 1 total; [bww['winner321123'/0, l='MpServer', x=-35.30, y=91.25, z=13.88]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bur.a(SourceFile:308)
	at bja.b(SourceFile:2069)
	at bja.f(SourceFile:764)
	at net.minecraft.client.main.Main.main(SourceFile:121)

-- System Details --
Details:
	Minecraft Version: 14w17a
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_51, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 416538872 bytes (397 MB) / 707788800 bytes (675 MB) up to 954728448 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 14w17a
	LWJGL: 2.9.1
	OpenGL: GeForce 8600M GT/PCIe/SSE2 GL version 3.3.0, NVIDIA Corporation
	GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Anisotropic filtering is supported and maximum anisotropy is 16.
Shaders are available because OpenGL 2.1 is supported.

	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: [Sphax Music.zip]
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	Anisotropic Filtering: Off (1)

Update your graphics driver to http://www.geforce.com/drivers/results/73784

Assuming no longer an issue.

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