This is the same link that scorp posted in another thread. And yes it should work for you. One caution however. The server kernel is supposedly optimized for server, not desktop use. I don't have any idea what the configuration differences between the server kernel and desktop are in the Ubuntu kernels. It would probably be wise to check in the Ubuntu forums and ask about the differences. The ideal kernel characteristics for a desktop and server are somewhat at odds with one another. Find out what you will be giving up to get the use of that last 500 to 800 MB of the 4 Gig. total on a 32 bit kernel.
You can of course compile your own 32 bit kernel with PAE patches for greater than 4 Gig. but you will take a bit of a speed hit when doing so. Of course if you are compiling a custom kernel you can probably make up this speed loss by customizing it to your equipment. For most I would say it probably isn't worth the effort to try to get the use of another 500 - 800 MB
You could of course install the 64 bit version of the distro, if all the programs you need work ok on 64 bit without a lot of configuring. But that is another issue which has improved greatly in the past year.
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