Won't Recognize Bootable CD

I am pretty much a novice with Linux although I have been working with computers for quite a while now. I have been toying around with a number of distributions trying to find one I like to run on an older laptop. I have run into a peculiar problem with Mepis (and PCLOS).

I have been able to successfully boot to Ubuntu 8.04 and openSUSE 11.1 Live CDs, however when I try to boot to the other Live CDs, the machine acts like they aren't there. It goes straight to the OS even if I bring up a boot menu and select CD-ROM. I can take those same CDs and boot to them on other computers without an issue.

I don't know if it makes a difference, but the laptop is an IBM Thinkpad A31.

Are they all the same make of disk? I have come across very "fussy" cheap CDROM drives that refuse to read certian makes of CD-/+R. IBM Thinkpads are generally of a high quality though.

I've had that happen before, (on a Desktop) it turned out to be a faulty RAM card that was preventing certain CDs from booting. In your case though, it might be simpler than that, could there be dust on the CD for example?

On IBM Thinkpads that I've worked on, DVD-ROM drives tend to read bootable discs more smoothly than CD-ROM drives (this might've just been a fluke in my case though)

Some older CD-ROMs won't read a CD even if there's just a few fingerprints on it. CD-RW drives are even harder to get good reads on, especially if they've been used to burn on a daily basis, that deteriorates the laser used for reading.

When you put the bootable CD into another computer, does it click, or pause during reading? That could be a sign that it wasn't burned properly (regardless of the brand of CD). You should try burning again at a slower speed, like 2x, it will take a long time, but will have less read errors.

You can also pull the Thinkpad's hard drive out, that will "force" it to boot from CD-ROM. As a last resort, you can try external USB CD/DVD-ROMs.

The hard drive should be behind the headphone jack, or maybe the infrared port... Use a small flathead screwdriver to gently pry the panel downward. They may be one screw holding it in place.

Hope that helps!