T31: can't boot from USB or CD/DVD

[bidibulle]

Hello
I have an old T31, it's working ok with Windows XP, but I wanted to test a Linux Live CD on it.
The problem is that the computer doesn't want to boot from the DVD or from a bootable USB stick.
The DVD and USB stick are working on other machines, I've checked.
I've also checked in the bios that the order of the boot is correcly selected: first: CD/DVD, second: removable hardware, 3rd: HardDisk.
The strange thing is that the Windows XP disk is starting when I insert it in the DVD reader: it's ready to install XP. So apparently all is working fine (except my Linux DVD )
I've created the bootable stick with unetbootin and the DVD with CDBurnerXP from an .iso downloaded on the internet (MD5 check OK).
I've also a T40, and the DVD is booting OK on it (installed Linux Mint Debian on it, and it's working really great)
So now, I don't know how to progress, any idea is welcome

[Neil]

If you burned your Live Linux CD on a CD-RW, you might want to try a CD-R disk instead. Many of those older optical drives just won't read RW disks, and many of mine have trouble with CD-R. Like you've found, they work OK with factory pressed disks, but not so well with burned disks.

Another option would be to but the T30 (or is it an R31?) HDD in the T40 and install Linux, then swap the drive back into the T30.

[automobus]

I have an old T31, it's working ok with Windows XP

You mean, Windows XP is already installed? If yes: does "T31" Windows read your recorded disc, that DVD which does not boot?

T31?

If T21: T21 does not boot from USB. T23 is first T-series to boot from USB.

If T30: insert Stick; enter BIOS setup; ensure Stick ranks lower (earlier) than internal HDD. USB Stick is not found in section "removable hardware"; it is treated as HDD, and it probably appears after internal.

[bidibulle]

If you burned your Live Linux CD on a CD-RW, you might want to try a CD-R disk instead. Many of those older optical drives just won't read RW disks, and many of mine have trouble with CD-R. Like you've found, they work OK with factory pressed disks, but not so well with burned disks.

Another option would be to but the T30 (or is it an R31?) HDD in the T40 and install Linux, then swap the drive back into the T30.

It's a T30, sorry.
And it's running correctly with XP installed (rather slow, that's why I wanted to install a light version of Linux).
I've inserted the CD of Windows to test the DVD/CD reader and check if the CD started automatically.
Sorry if my message was confusing, my english is a little rusted.

Neil's diagnosis and remedy are perfectly correct.
I've burned the .iso on a DVD-R instead of a DVD-RW and it's working. The DVD boots and I can install Linux now.
So, thanks a lot Neil, I'm really grateful to you, I wouldn't have thought of that solution myself

If T30: insert Stick; enter BIOS setup; ensure Stick ranks lower (earlier) than internal HDD. USB Stick is not found in section "removable hardware"; it is treated as HDD, and it probably appears after internal.

Thanks a lot, it's also working.