Infinite loop on boot (with some exceptions)

[MeanMrVile]

Hi everyone, I've tried searching both the forums and the wider web but not quite found anything relevant to this (though I suspect it's probably the etymology that I'm using so I apologise if this is something I could have otherwise easily have found - any direction greatly appreciated).

I'm not quite a newbie but I'd say I'm more of a "user" than a "mechanic" (I've dabbled under the hood but not as much as I'd like/want to), so hopefully this makes sense:

Did a fresh install of Mint on a Lenovo Thinkpad (c. 2015). All seemed good, after rebooting I went about personalising (just adding/removing common packages, nothing heavy).

Shutdown yesterday and returned earlier today though now as soon as I get the initial flash screen with the Lenovo logo, it does not progress past before rebooting, unless I enter BIOS setup. No matter what I do in the BIOS though, it restarts again after exit.

Using both live CD/USB is ineffectual; if I choose to boot from either, I go straight back into the loop above.

The only exception is if I remove the HDD and try a live CD/USB, and only if I manually select to boot from one of these options, I will be able to enter the Mint (or gparted etc., tried other distros to check) live environment. If I leave it alone on boot, it doesn't seem to go through the boot order (vacant HDD/CD/USB/Network) and returns to the boot loop.

I've tested 1 other HDD (Windows, it was spare and I *think* is in working order as I used it recently, plus connecting it via USB to my Windows desktop picks it up OK) and the problem is replicated in the Lenovo.

I tried a CMOS battery reset which changed the BIOS time and nothing else (some settings seem to remain disabled).

Typing this out I realise it's likely some sort of hardware problem rather than OS-related.

The only thing I've done differently this time compared to other installs in the past is I did manual partitioning (I left some free space as I was hoping to give Linux From Scratch a go).

I would be most grateful if anyone might have any suggestions as to what troubleshooting I might look into?

Best wishes,
Stu

[Termy]

It certainly sounds like a hardware issue, unfortunately. I appreciate that you made the effort to try to learn about and remedy the problem yourself, even searching these forums. Resetting the BIOS via the CMOS battery was a good idea, and probably what I would've tried. I wonder if the S-ATA port on the motherboard or the S-ATA cable is faulty, which would explain why both drives are having problems.

Do you hear sounds from the HDD when plugged into the laptop? If you hear absolutely nothing from it, it's possible it's not getting any or enough power. It's a shame it's a laptop, as it's makes replacing parts a real pain in the behind. Is it still under warrantee?

[MeanMrVile]

It certainly sounds like a hardware issue, unfortunately. I appreciate that you made the effort to try to learn about and remedy the problem yourself, even searching these forums. Resetting the BIOS via the CMOS battery was a good idea, and probably what I would've tried. I wonder if the S-ATA port on the motherboard or the S-ATA cable is faulty, which would explain why both drives are having problems.

Do you hear sounds from the HDD when plugged into the laptop? If you hear absolutely nothing from it, it's possible it's not getting any or enough power. It's a shame it's a laptop, as it's makes replacing parts a real pain in the behind. Is it still under warrantee?

Hello, thanks a lot for the reply, regarding CMOS; not sure whether or not the answer lies here but I realised there's an 'Administrator' password. I enter no password and it let's me in with limited options (e.g., excluding anything meaningful like boot order). Unfortunately it's an old work laptop that we are (legitimately!) allowed to keep after so long (this one is now 2 iterations behind the upgrade cycle) so I will try to find out what this password may be as hopefully there's a record somewhere, unfortunately we have a somewhat decentralised IT Services team so such records might have left with staff! Otherwise Lenovo suggest/insist on a replacement motherboard. I've tried some of the suggested default passwords that are posted online but no luck (I'm not surprised, my organisation is rightly quite security conscious).

Plugging the HDD in it spins up and I can feel it vibrate. I think you're absolutely right though it's got to be a hardware fault - I'm slowly creeping my way through disassembling (the SATA interface is fixed under a block of plastic and seems to be one of the last things I can possibly get to - I'm trying to not 'physically' brick it in the process).

Appreciate the advice!

[AndyMH]

With an admin password set you will not be able to change the boot order. I bought a second-hand T430 off ebay, found it had a locked BIOS, the seller swapped it for another one. Depending on the model you may be able to reset the BIOS, requires shorting out a couple of pins on an IC on the motherboard. Not for the faint hearted.

[Termy]

I'd have thought resetting the BIOS/UEFI would've scrapped the password, as it usually does. I suppose it's possible the default settings include a default password.

[...]

Resetting a BIOS/UEFI is usually as simple as removing the CMOS battery, turning on the machine, then inserting the battery. The small Li-ion battery allows the BIOS/UEFI settings to be stored in the CMOS for many years. Some modern motherboards have switches or buttons to reset the BIOS/UEFI more easily, with some even restoring the BIOS/UEFI to its default firmware, such as following a broken update.

[AndyMH]

You may get lucky removing the CMOS battery, suspect not. If it was that easy there wouldn't be much point in having an admin password in the first place.

OP - you haven't said what thinkpad model you have, suggest you google you model and 'remove supervisor password'. An an example this is what you have to do to remove the password on a T430:
https://htr3n.github.io/2019/06/t430s-s ... d-removal/

Your other route to information is join the thinkpad forum and ask there, not as active as the LM forum, but some people who know their stuff:
https://forum.thinkpads.com/

[Termy]

You may get lucky removing the CMOS battery, suspect not.

Unless a manufacturer or business for some reason have a default password or some other piece of hardware and software handling the password alongside the BIOS/UEFI, then what I said should apply. Anecdotally speaking, I've had and seen such passwords on systems before, where resetting it was as simple as the thing with the CMOS battery. After all, how does it remember the password? Often the battery powering the CMOS. Again, that's assuming it's remembered as a direct result of the power from the CMOS battery. I'm 37 and going by old information, but looking online to double-check seems to yield the same result.

Some CMOS batteries are soldered to the board, apparently (weird ), in which case I'd certainly be using the correct jumper to reset it.

If it was that easy there wouldn't be much point in having an admin password in the first place.

That's why sensitive machines are usually physically locked down and watched over. Besides, if someone has access to the inside of the computer, then them fiddling with the CMOS battery is the very least of your concerns. This reminds me of my school days, when people would sneak into the library machines to swipe the drives. I think a BIOS/UEFI password is more of a deterrent and to slow down ne'er-do-wells.

[MeanMrVile]

Hi Matt and Termy, thanks for the continued advice: it's a T440p. I did have a look for options and aside from the possible generic passwords I stumbled across shorting the pins, though thought I'd hold off for the moment at the risk of bricking it with my tinkering (plus there's at least one final screw/latch that I am struggling to find that's preventing full access to the motherboard - all the good stuff seems to be covered at the moment).

From what I can find online it seems likely that the supervisor password is independent of the CMOS battery on this model; still trying to find someone that might know what this was set is (I do now know that it's our IT Services that set these, though there was no systematic approach and supervisor passwords were set locally - d'oh).

So I booted live Mint via the offending hard drive SATA/USB on the Lenovo, and installed to the same drive and all went well and it continues to boot/work fine... I feel this probably suggests the problem is the SATA connection rather than anything else. I'll have one last go at getting to it and (hopefully) testing it somehow and see if that works.

On a side note, in a generally technically-minded department full of tinkerers I think the BIOS password has always been a thing to cut down on frustrated call-outs to staff that are supposed to tinker. The only other hand-me-down I've had was a very old Dell Optiplex c. 2014 which I just needed to swap the "pwd" jumper pin around on! Funny that at around the time a few work experience guys were hired to deal with the donkey work of swapping the Dell's for HP's - one (or more) of them were smart enough to take out all the HDDs, RAM and processors as they undertook this... only came to light because that's exactly what the older IT hands were planning to do on the sly!

[AndyMH]

If you haven't got it already:
https://thinkpads.com/support/hmm/hmm_p ... 467_01.pdf
Tells you how to replace every part. And, congratulations, you got what I think is the last thinkpad with a socketed CPU, so you could swap out the i5 with an i7. Got a friend in Aus who has done that, but he has had some temperature issues. I've done the same with my T430 and it runs about 10C hotter.