ATA Card and CPU Utilization

[techem]

I was about to buy a Seagate 80GB Barracuda ATA IV with a Maxtor ATA/100 PCI card as an upgrade to my BH6, PIII/800, 512MB RAM. Then I noticed some benchmarks that show a large increase in CPU utilization on systems with these cards. My BH6 supports ATA/33. Should I just use the Seagate on the built-in ATA/33 bus (without buying the card) or will the CPU hit with the ATA/100 card be worth the drive performance increase? In other words, is it worth it to add the card? I currently run Win98, but will be upgrading to Win2k or XP when I replace the drive. I only plan on having one HD on the ATA bus for the forseeable future. I'm sure my next mobo will support at least ATA/100, so the card will be temporary.

Thanks for any insight.