If you are talking about support for any raid devices created by this controller, then I would highly recommend going with a more modern distro, like Fedora http://fedoraproject.org/. As the others say, the new kernel and dm-multipath versions have support for this controller.
Fedora 12 was recently released, and I can confirm it has support for this raid controller. You can try a "Live" version that can boot from CD/DVD or a USB drive, without touching your harddisks. You can also try another Live distribution like PartedMagic: http://partedmagic.com/ I've used 4.5 and it properly detected a raid0 on this controller. Previous version of Fedora and PartedMagic only showed the individual drives, even though they were in a raid.
A quick note, since support was recently added, I know it isn't in Red Hat Enterprise Linux 5.4 (this is what CentOS 5 is built from), and it absolutely would not be in CentOS 4. RHEL (and thus CentOS) are built from stable Fedora releases, meaning anything in F12 would not appear in RHEL/CentOS until version 6. Check the timeline here: http://en.wikipedia.org/wiki/RHEL
The latest RHEL/CentOS are based on Fedora 6, which was released in 2007. RHEL/CentOS 4 were released in 2005.
From what I see of that machine, it was designed for use as a server; the problem will (probably) be motherboard chip-set support in the Linux kernel.
Check you don't have motherboard RAID enabled and the drive is connected to a normal SATA/SAS/PATA port; failing that, the best chances are to try installing a PATA drive (if the machine supports it), failing that try a SAS drive (I'm guessing that SCSI support is better than SATA, but could easily be wrong); if that fails the only option is to update the Linux kernel (which means using a later build) or use another PC... unless anyone else has any ideas?
It's always *possible* to install a later kernel (and any dependencies) without actually changing the system too much. You can boot into the new kernel and see if your hardware works, and always back out and boot into your old kernel. I've done this with a Fedora kernel on a RHEL system before. Another option is to virtualize your CentOS install using something like Fedora or Ubuntu KVM or Xen virtualization, but you could end up needing access directly to your hardware so that might not work.