Problems with new laptop : hardware or software ?

I was so happy to have a new laptop to test and install… but now I’m really pissed : the laptop crashes for some unknown reason.

It looks like there was an immediate shutdown (like cutting off the power), in the middle of a work session, and without prior symptom of a problem, and of course everything I’m doing is lost.

I wonder if it’s a hardware problem or linked to some software bug or misconfiguration somehow… The machine is brand new, and did work allright for the first week, although I was not doing intensive stuff all the time (basically mainly testing what needed to be installed to run a Debian system on it).

Maybe this would be related to a bad support of some sort of hardware in GNU/Linux ? … I’ve experienced this crahses on 2.6.11 and also on 2.6.8…

Strange, and until now, the Dell diagnostic tools are working well : all tests passed… maybe the machine is not up long enough for it to find the problem ? … or it’s because this happens only with Linux and not with Windows 98 ? … how f*ckin annoying this kind of situation can be !

Update : Maybe this is caused by some kind of problem on the AC adapter side. After a power spike or something like that, it’s possible that the AC adapter shut itself down, which causes the system to run on the battery… after a while, the battery empties and the machine suddenly shuts off… I may not have noticed that if I had no battery applet around… I’d better configure some sound alarm of some kind when APM events occur…

Update 08/08/2005 : Now, I have other ideas about this problem… :

First, the problem also appeared when running on battery… so it’s not the AC adapter’s fault… maybe the battery ?
Second : I tried and use the same hard disk (hence the system) on another identical machine, in case it would be the OS/software… and it turned out that the same problem happened on the other machine. So this may well be related to software… or the harddrive ?

Something else I noticed is that the latest crash occured when the screensaver was active, displaying a 3D molecule… and it reminded me of problems years agon on machines when 3D hardware acceleration was activated…

I’ve then turned off the DRI support in my XF86Config-4 file, and will see if this has an impact on the problem, and maybe fixes it ? In the meantime, I opened a ticket at Dell… and they suggest I check the RAM banks… I’ll try that also… and will keep my blog posted.

Update 09/08/2005 : Completely new hypothesis : actually, it turns out that it could be a problem with the power and a defective home-made multi-plug…

It looks like there was a short circuit in one of the multi-plugs on which my laptop was plugged, which led to having +25 V on the ground wire (external contact) of the adapter’s output connector … and so these 25 V between the external metal parts of the laptop (like the anti-theft cable locked on to my laptop, or the border of the keyboard) and the ground…

But it looks also like the AC adapter was not protecting the laptop : having tried an old adapter from a collegue, I found out that the old one maintained 0 V whereas the new one
would not. Although one should not use deffective multi-plugs, and would expect 0 V on the ground wire, I think there is anyway a problem if the Dell AC adapter is not protecting from such a situation.

So I suppose that the problem of laptop shutting down instantly at random times actually occurred when I was touching it, maybe myself carrying some static charge of some kind, when my watch metalic bandwrist touched the anti-theft cable lock, thus leading to an increased short circuit that the laptop’s hardware detected…

I hope this is the end of the trouble now I have removed the faulty multi-plug, but I will definitely try to get a more protective Dell adapter.

Tell me what you think…

Update 09/08/2005 bis : Well, it looks like it may not be the adapter’s fault, since it happened again… but this time without the faulty multi-plug…

Well, this time I’ve decided not to use powernowd, just to check if this changes anything…

Feeling desperate

Update 10/08/2005 : This time I can for sure say that there is a problem with the hardware, which is not related to using GNU/Linux : as my machine was booting, and still in the BIOS stages, I touched the anti-theft cable lock with my watch again, and bingo : shut off. Dell is going to replace the motherboard. I hope it will get rid of this problem. Too much static charge on me and may watch ? Too sensitive motherboard ? … anyway, I think I will try to pack the cable’s lock in something plastic to protect the computer from direct contact with the internal metalic parts.

Update 23/08/2005 : I think we have a workaround although no definitive solution. See my latest post on the subject.