resp0nd,
Why type of IDE cables are you using for your CDROMs? Are your IDE CD ROM drives cabled and configured correctly (master, slave or CS if you have a Cable Select cable)? Are you using 80-pin EIDE cables - not the old 40-pin cables?
Go to:
http://dlsvr03.asus.com/pub/ASUS/mb/...906_p5p800.pdf
Open this up (will take awhile - 4+MB PDF file), and jumpt to page 45 - scroll down and read about the IDE setup. Also look at page 47 as this gives info about compatibility between various BIOS settings and potential SATA/IDE device configurations depending on the version of Windows installed. Unfortunately - this is a "Pre-Vista" board - so the documentation don't talk about Vista issues.
AUTO transfer mode should work - but you need to use 80-pin EIDE cables on all of your IDE drives as those 40-pin cables will not support higher UDMA transfer speeds.
Read through pages 74 thru 76 in that manual I linked you to above. I'm thinking something might be configured incorrectly with these drive-related BIOS setings. Look at the PCI IDE Bus Master setting on page 87. If it's enabled - try to disable this setting and see if you have different results.
Try JUST connecting your 2 IDE CD ROM drives with NO hard drives and see if you can bring up the BIOS Setup and see if both drives are recognized. Try the same with just your two SATA hard drives (NO IDE devices).
dai brings up a good point - if the problems you're having aren't due to incorrect BIOS settings, drive jumpers or cables, this might be an issue with your PC power supply's ability to simultaneously provide adequate power to ALL of those drives. Trying just 2 CDROMS with NO hard drives and visa/versa should help you determine if there's a power supply capacity issue. If you BIOS is able to detect those drives in either configuration - you might have a power issue.
Lots of stuff to try and consider - but hopefully, this info will shed some light on the problems and limitations you're having with your motherboard and drives.
- John