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Despite BIOS setup, can't boot from CDROM

Despite BIOS boot sequence CDROM,C,A i can't boot from a bootable CDROM for system installation, for instance.
 I do already sense that BIOS may have no effect since first SCSI is loading ( CD ROM is SCSI ) & then says
" BIOS not installed " . I also tried boot sequence SCSI, C, A but no go. So how will I convince my CDROM SCSI to boot
the CD's first when I run up my machine ?

For those who like to read between the message lines:

it goes:

SCSI devices detected . . . then

BIOS not installed . . . then some

DPI pool . . .then

loading GRUB bootloader

Any idea ?


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3 Solutions
You will likely not be able to boot from a SCSI CD-ROM drive. Most older SCSI cards and chips (and many new ones) just won't do it. You can try your SCSI card maker's web site to see if they mention or support that feature. Can I ask what card it is?

An IDE CD-ROM drive can be had for about a handful of dirt, so that could be one way to go. (I have a system with a SCSI CD-ROM and SCSI CD-RW.)

But the best way to go is probably a boot floppy with SCSI driver for whatever OS you need.
Hi xberry,

It looks like your SCSI card doesn't have a BIOS. The PCs Bios together with the SCSI Bios will enable your computer to boot from a SCSI device.

... or if it has one it is not enabled. In this case you have to go into the setup of your SCSI
card and turn the BIOS on
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Have you tried updating the bios of the machine in question?  If you have an option, in your bios, to be able to choose SCSI as your first boot device than you should be able to boot from it.  I would go to the hardware vendor's web site, get the latest bios update and then try it again.

If that doesn't do it than it may be the cd your trying to boot from.

Have you tried booting from another "bootable" cd?

xberryAuthor Commented:
Likely Chris & griessh are right:

My SCSI card is from Adaptec with AHA 2840.
It should have it's own BIOS because I can access the Host adapter /SCSI settings when running up the PC (with ctrl-A)
though . . . I can't find any option to turn the BIOS on there.

Booting with boot floppy did always work in the past & still does but since there is bootable installation CD's available these days,
I started to ask . . . : )

to maker 10: please read my question again, I have a good dozen boot sequences available there in BIOS, included SCSI, CDROM & ZIP & . . .  it is not the CD, since it is same with all bootable & . . . they do boot up on friends comp with IDE CDROM.
Does it have an EPROM on the board? There is a BIOS available at http://www.platys.com/worldwide/support/driverdetail.jsp?sess=no&language=English+US&cat=/Product/AHA-2840A&filekey=284x.exe , but you have to burn in yourself.

Download the installation manual from :


Check out the note at the bottom of page 3. It basically states that only hard drives are controlled by the BIOS.
I believe it is as follows: Essentially you cannot boot directly from a SCSI drive unless it has a bios of its own. The reason is that normally the SCSI drivers are loaded during the normal boot sequence and since that doesn't happen if you try to boot from a SCSI drive, the SCSI drive can't be used at that stage of the boot sequence. The IDE drives on the other hand are under the contol of the bios which is loaded at boot up. The way round this is to have a SCSI board which has its own bios and to have that SCSI bios enabled - as already mentioned - if its possible on your SCSI board.

Please let us know the precise SCSI make and model number of your SCSI board and we should be able to find out whether it can do the job.
Apologies you already gave the details of your SCSI card.

From Adaptec's website there is the following info:

"Include in BIOS Scan  
This option allows the user to determine which device the host adapter is to use as a boot device. The Default is Yes. To utilize this option the Host Adapter BIOS and Dynamically Scan for SCSI Devices must be enabled."

So your Adaptec SCSI card can do it but it needs to be enabled. The chances are it has been disabled so as to speed up the whole boot sequence. You will need to get into your SCSI software to do this as there is no instructions about jumpers etc.
xberryAuthor Commented:
But what about the information from Adaptecs installation guide where it says that CDROM & other non hard disk device cannot be controlled by the host adapter BIOS (see lidskys comment, !)

Looks as if Chris Schumanns comment, apart from lidsky still giving most enlightenment here.

I go through my SCSI setup options again to see if I missed anything, but why not to believe the manufacturers information ?

xberryAuthor Commented:
Have to apologize since I did a little typing mistake, the 2840 should be 2940 but in effect this doesn't make a lot of difference.
From the Adaptec manual:

" if both SCSI & non SCSI disk drives are installed the non SCSI disk drive is always the boot device"

So likely I'll follow Chris Schumann's advice & get an IDE connected CDROM/DVDROM in future.

For now in case of installations, boot floppies still do a good job.

I'll also reward some points for the links to Adaptec site. Thanks.
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