Why is Minecraft so slow?

[Cam!]

I removed OpenJDK and installed Sun Java, but still, I'm getting a lot of problems. The app itself launches fast, but when I log in, I see the Mojang (developer) logo for at least 1-2 minutes. Then, I'm able to launch a world. When I'm playing, there's substantial lag. My specs are high-end, too.

What should I do?

[mmsmc]

please post your specs

[Cam!]

It mostly has to do with your Java + CPU.

CPU: Intel Q6600 (Quad Core, 2.4GHz)
RAM: 4GB
GFX: ATI Radeon HD 4850 (Although no proprietary drivers are in use. I'm using 11.04 Alpha 3.

[keltic dave]

Can I ask why people have such problems with openJDK. I run minecraft just fine with it no slow down or anything infact I find the stability much better than my experience using minecraft on windows.

Anyway you shouldn't be getting any problems at all unless you're running it on 64bit OS distro.

[Cam!]

I'm running it on 32-bit 11.04 Alpha 3. Even on 10.10 it was laggy.

[keltic dave]

I'm running it on 32-bit 11.04 Alpha 3. Even on 10.10 it was laggy.

this might be a shot in the dark but it could be ATI. I use Nvidia as driver support for that seems far better.

[Cam!]

On Windows, my ATI card works fantastic.

[Nutbun]

I run it on 64 bit Ubuntu and a ATI card, and it runs great.
Maybe you haven't installed the additional graphics drivers.

[keltic dave]

try doing this then

go to the folder you have the minecraft.jar in create an empty file name it run.sh then copy this code into it.

java -Xms512M -Xmx1024M -jar Minecraft.jar

[Cam!]

I run it on 64 bit and a ATI card, and it runs great.
Maybe you haven't installed the proprietary ATI drivers.

Every time I install the proprietary ATI drivers, it renders Ubuntu useless. I can't get to the log-in screen without a graphical glitch or the monitor turning off.

Also, what folder do I put it in? The folder that has my Minecraft shortcut, or the Minecraft folder with all its data?