Recently, I've been trying to create a multipurpose Bootable DOS CD to aid in diagnosing and repairing simple PC problems. So far I've managed to add USB support, long file name support, and a host of DOS utilities. (I have a boot menu to enable or disable these features.) And I can get it to boot successfully in most modern PCs. HOWEVER, I want this boot CD to be UNIVERSAL and for some reason I can not get it to boot at all in old PCs such as my ATX unit with an ASUS P5A mainboard - even though boot from CD is enabled in the BIOS. It just skips the CD and boots straight to the C: drive.

BTW: This is a "Pentium Super7" (Socket 7) mainboard dated from about 1999 and installed with an AMD K6-2 500. I know it supports boot CDs because I am able to get this old unit to successfully boot other CDs, including "Boot CD+" and other DOS-based utility disks. The "Boot CD+" disk includes the following two boot image files:

BOOTCAT.BIN
BOOTIMG.BIN

And these two binary files appears just like the two files found on CDs I create with Roxio Easy CD Creator 5.

The method I've been using to create a bootable CD is via the "Bootable CD" project option in Roxio Easy CD Creator 5. Specifically, I've been doing it through the "Floppy Disk Emulation (1.44 MB)." I have not yet tried either the "Hard Disk Emulation" or "No Emulation" because it would require a lot of work to edit my complex batch files and change all the drive letters.

Do you think either "Hard Disk Emulation" or "No Emulation" would have a better chance of success? And Roxio Easy CD Creator 5 gives these two options for bootable CD creation:

"Generate Image from Floppy"
"Using Existing Image File"

I've tried both methods and neither seems to work in my ASUS P5A. Perhaps I should try a different program to create my bootable image file? Please, can somebody recommend another method to create bootable CDs? (Preferably something done with either freeware, shareware, or a demo...)

Even though I could not get this CD to boot on my old ASUS P5A system I could get it to read the CD from either DOS or Windows 98SE. And I burned this onto a CD-R, not a CD-RW. That said, the CD-R I burned it on is really old media. (Maximum 4x burning speed and about 8 or 9 years old!) I burned several copies on this old stuff, but while they work on modern machines it won't BOOT on my old system. I may try to burn it on more modern media to see if that will work.

Please have a look at Hiren's BootCd

You are basically needing the generic CDrom drivers, ideally the same Cdrom drivers that Hiren is using

I have created many (really hundreds) of bootCds, and I have at last made one that seems to be very universal, except the legalities stop me from uploading this 700Meg stacks of programs (both DOS and Windows menu) CD.

These days BartPE seems to be the go, except it doesn't work well on 98 (and that's why I like mine)

I will answer any questions you have, if you like.
But I want you to put the A floppy emulation, CD divers on it first !

Edit:
By the way

instead of using more and more CD's (as I did)
Use the floppy to boot the computer with the present CD drive in as well (but start from floppy)
The floppy will boot and read the CD as it goes without fuss, and you are only editing the floppy then, not the CD
Once you get the boot floppy right, you can then create an image from it, and use it to create the CD

Also, once I got the floppy working (took about 3 months on 1.4Meg !) You can then turn to Windows menus
That way, you can have CD Dos bootup menu, and Windows autorun menu
I even put the linux "password recovery" on the dos menu, plus Ghost plus Partition Magic and stacks of others (it's very big !)