Can't choose between the IBM Deskstar 75GB and the Maxtor DiamondMax 80 GB...Any thoughts. Also, would I have to get an Ultra 100 card with both, or just the Maxtor?
That's not quite true. Since IDE HDs are yet to break a STR of even 40 MB/sec, ATA/66 support would would and using ATA/33 would even work with a very slight decrease in performance.