Sun Blade 150 - I can't hook up extra drives

I'm not familiar with this particular machine and it's baffling me. For those that are familar with the workstation, allow me to paint a picture. If you were looking down on the machine (open) you would see the main board and then a riser board. On the left side of the riser board are jacks including an IDE jack. On the right side is another IDE Jack. The right side is where the single hard drive and CDROM are connected.

What I can't figure out is why when I hook up anything to the left side of the riser board, the machine will NOT boot. In fact, the hard drive doesn't even spin up when it's conntected on the left.

And when I connect a 2nd IDE drive in place of the CDROM (center of the ide cable), the OS doesn't see it when i run the "format" command. I have the HDD in the middle jumpered to slave, and the HDD on the end jumpered to "master w/ slave"

My goal is to hook two hard drives up to this machine which i'm using to learn Solaris 10 and become certified. I don't belive there is an malfunction, as I have two other Blade 150's and they behave the same way.

I just went through the same thing on my Sunblade 100 (same box). If you look at the riser where the IDE cable plugs into, there's a 2nd connector under it. You can hook you boot drive to IDE 0 and your CDROM and 2nd drive to IDE 1. Use standard IDE ribbon cables. also, don't for get the jumpers on the 2nd drive must be set as slave. Restart back to your original settings, make sure your box woeks and then go step by step setting up the drive. also, at the ok prompt, run reset-all and then probe-ide to see if your drives show up.