When I was using CentOS 5.1 x86, it had no problems seeing all 4GB of memory. With the new Ubuntu 8.04 x86, it only shows 3.5GB free. I loaded the /boot/config-`uname` in menuconfig and the default configuration shows that 4GB memory support is enabled, along with PAE. So what gives? Why only 3.5GB?

This is probably not what you want to hear but with 4GB of RAM it would make sense to install the 64 bit version. It really doesn't make much of a difference anymore. I'm sure that you know what you are doing, it just seems a bit counterintuitive.

And yes, it does look as if PAE is enabled as 3.5GB is already more than the default kernel will support. Did you try the linux-server kernel?

I have recompiled my kernel for 64GB of RAM and I can see all 4GB now.

Thanks! I will recompile my kernel with the 64GB option. I just found it odd since the original Ubuntu config file already shows 4GB memory support with PAE. On my old CentOS 5.1 32-bit system, I also had it on 4GB memory support with PAE and it saw all 4GB.

I gave up on Ubuntu 8.04 because I could not compile the kernel. I got all these errors, and I am not familiar with compiling a Debian/Ubuntu based distro.

So, I decided to try Fedora 8 and I had the same problem with Fedora 8 only seeing 3.5GB instead of all 4! I am going back to CentOS 5.1. It was fun while it lasted, I think ...

Bummer, that's what I like Slackware, you can do anything with it.

Never tried Slackware. I couldn't even download Slackware. When you go to Slackware.com, there is no download section. Very odd!

As for being able to do it all, I'm sure there was a way to compile a kernel in Ubuntu since I did read many "how-to's" online. I kept getting some kind of asm.c error when issuing the 'make' command. Never experienced problems compiling kernels in CentOS. CentOS is so straight forward: make, make modules, make modules_install, make install. Done! None of this apt-get huh wtf lib1337 followed by a dpkg -i -v -a -z -l -1 -b -c --comment=-blah --huh /root rm -rf kernel-2.9.999 stuff followed by a sudo fakeroot kernel-2.9.999 --comment=more options /aaaaa

Here it is, the section is called Get Slack:

http://slackware.com/getslack/

Pick a mirror close to you........Happy Slacking

How did you make it?
Any step-by-steps?
Is there Ubuntu 8.04 LTS Desktop?
Thx.