How-To "Get a BOOT menu" on a Tyan Thunder server (S2462)

This is the GOAL:  To be able to BOOT to a bootable CD-ROM disc

Does anyone know how to FORCE a 'pause' the POST process of an Adaptec card, so it will bring up a "boot menu"?  I've done this one time, but I cannot seem to do it again.

So, I have a Tyan main board inside a 3rd party case (with a 3Ware SATA RAID controller) and lots of hard drives.  The system has a 36 GB SCSI OS drive and a SCSI CD-ROM.  

NOTE:  There is NO mention during POST on how to access the BIOS of this server (no DEL, F10, pgdn, F12, etc.).  I've tried them all time and time again.

When there is a known boobable CD-R in the SCSI drive, during POST, an additional note comes up on the screen telling me something like:

"A bootable CD-ROM has been detected"

This is followed by a bunch of HEX code and then finally something like:

0.  Default boot entry (SCSI CD-ROM)

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After this, The Windows OS starts everytime.

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One time, I hit so many different combinations of keystrokes that a (blue/white) DOS menu appeared asking me what device I wanted to boot from.  This was very similar to the screen you get on a Dell PC after hitting F12 for the "Boot Menu".

I've never been able to duplicate getting this boot menu again.

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I'm convinced this is tied into the Adaptec controllers on the Tyan board (I have two one them).  The OS hard drive is one one, and my CD-ROM is on the other.