I've got an AGP Quicksilver 733hz which was created/shipped in 2002. It's a long story but I guess it's a 2002 that's not a 2002. When I ordered it I had Apple install a SCSI card to use some SCSI periferals which are now dinasaurs/boat anchors.
Anyway it's got a 50 pin slot on the underside of the card for internal devices.
I've maxed out the 40GB master drive and a little 10GB I threw into position 3.
What I want to do is toss the 10GB, and add two more drives with as much speed and capacity as I can get.

The Apple tech specs say the following about what I can put in it:
Three 3.5-inch (90 mm) hard drive expansion bays:
-One ATA drive preinstalled on standard configurations
-Support for up to two internal ATA drives
-Support for up to three internal SCSI drives
-Support for a combination of internal SCSI and ATA drives (up to one ATA and two SCSI)

It doesn't say I can put in 2 ATA and one SCSI, however. Why not?
I heard there's some controversy about G4's not being able to handle drives larger than 128GB. xceller8yourmac has some entries on that issue but I'm still scratching my head about that. Apparentyl some folks haven't had any problem whereas others end up with unmountable drives.
What can I do? Can I put in a 200GB ATA and SCSI of whatever size I can afford? Do they both have to be under128GB if I still use OS9?