Matthew,
  The "hardware" RAID that is built into most desktop motherboards (including yours) is not really hardware RAID it's software RAID in bios.
Running with software RAID in Linux is actually better than the horribly limited BIOS-based software RAID.  The onboard RAID in consumer motherboards is intended to allow gamers to run a limited RAID in Windows, it's a waste of MB space and power for Linux users (and I prefer machines without it, except there aren't many available any more).
Real hardware RAID is important in server systems when the reliability is critical and the better performance with external arrays is worth the extra $1000 or so for a real ASIC-based battery-backed hardware RAID card with it's own cache RAM.  For home use it's just not worth it.
Software RAID is pretty effective in Linux, and you'll almost certainly be fine with performance unless you're running an ancient single-core CPU or a tiny little atom chip.

==Joseph++

Matthew A Coulliette wrote:
> Hi all,
> 
> I was trying to install Ubuntu 9.10 on my new Dell Precision M6400, that
> I bought from the Dell Depot.
> 
<<Details Snipped>>>
> 
> If anybody knows how to setup hardware raid with ubuntu 9.10 (karmic
> koala), I would love to hear about it.
> 
> MatthewMPP