External DVD drive query

I finally bought a new external USB DVD drive after weeks of trying to get my old internal DVD drive to read DVDs, but in the end it was no go.

With the new one there are a couple of issues, like near the start of a DVD sometimes there is some freezing for 2 seconds before the DVD resumes, usually without further ado. If I go back to the point where this occurred then it normally plays OK the second time around. This occurs on my newer DVDs as well as the older ones, and sometimes DVDs play without any issue.

One other issue is with CD-ROMS. I have a few of these left over from years ago when I used to boot from them, whereas today I use pen drives for that job. So booting from CD-ROMS isn't that important any more other than to provide a back-up should any of the USB drives fail. But none of the CD ROMS now will boot as they used to do with my internal drive. No doubt, there's a technical reason for that. For a start my BIOS doesn't even see this USB DVD drive, but can still see my old DVD drive as that is still connected internally to a SATA port. So there's one reason. But even if I make the USB drive the first device to boot from, then pop a Windows 7 installation disk in the tray, my PC still won't boot from it. But I'm not that concerned - just like to know why it won't be booted by the new drive. But once I'm booted to Windows 10 or Linux, all CD-ROMS can be read and the files opened in the drive.

2nd paragraph
That is an indication of the drive having difficulties reading discs.
Possible reasons for that.
1. Optics in drive need cleaning.
2. Old stocks of Writable/re-writable discs, manufactured discs, deteriorating over the years.

3rd paragraph
1. and 2. also apply.

Depends on your hardware, old boot discs should be re-made for UEFI secure boot etc on new discs be they CD or DVD. I use CD-RW and DVD+RW initially so as not to waste a load of write once discs.

You need to check those old discs, there are aging processes on both the manufactured discs and those writable ones with a dye layer. Printed or stuck on labelling is also a factor.

I use an old scanning application for CD/DVDs retained from around 2006 in W10 compatibility mode with a maintained optical drive.

Helmut said:

2nd paragraph
That is an indication of the drive having difficulties reading discs.
Possible reasons for that.
1. Optics in drive need cleaning.
2. Old stocks of Writable/re-writable discs, manufactured discs, deteriorating over the years.

It's supposed to be a brand new drive, bought off Amazon, so should hardly need cleaning. I only started testing it 2 days ago. I'm ruling out 'needs cleaning'. If it had been extensively used then maybe. So either it's faulty or the DVD has too many scratches/marks on them, But there are few of these from inspection of my disks.

3rd paragraph
1. and 2. also apply.

Depends on your hardware, old boot discs should be re-made for UEFI secure boot etc on new discs be they CD or DVD. I use CD-RW and DVD+RW initially so as not to waste a load of write once discs.

You need to check those old discs, there are aging processes on both the manufactured discs and those writable ones with a dye layer. Printed or stuck on labelling is also a factor.

I use an old scanning application for CD/DVDs retained from around 2006 in W10 compatibility mode with a maintained optical drive.

Those few CD-ROMs were all working fine and booting up from my internal DVD drive 2 months ago until that went kaput. So I find it hard to believe all of them have suddenly deteriorated as to no longer being bootable. There has to be another reason - eg are CD-ROMs only supposed to be bootable from internal drives connected to SATA?