I am having the same problem too... or very similar. The system is a NetVista- not exactly sure what model (I'm not near it right now, I can get more info on it tomorrow). It is running Windows Me. I don't know when the problem started, because I haven't used the computer for months. I'm not sure if anyone else has (it is at my business, but it is rarely used). But I just found out about the problem today. Anyway, the system restarts before it gets anywhere in a normal boot (just when the Windows Me splash screen comes up). In a safe boot, it will ocassionally reach the desktop, load the system tray, and start to load help... at this point it will restart. Sometimes it restarts sooner than this, sometimes it doesn't even get past the Windows Me splash screen in safe mode.
I created a emergency boot disk from a laptop running Windows 98... and the Netvista has the same problem when started from this disk. It won't even boot into Safe Mode using this disk, although I can get it to boot if I try command prompt only safe mode (however, normal command prompt only does not work). I have also had success doing a step-by-step boot from the Windows 98 emergency boot floppy... if I say yes to every step, it will drop me at the command line, but I have tried running both scandisk and scanreg from here and both end up causing the system to either reboot or freeze. So basically, I can get to the command line, but can't run anything useful. When I reach the command line through command prompt only safe mode, I can't run anything useful because himem.sys isn't loaded.
I have tried going in to the IBM diagnostic tools (pressing F11). This will load, and present a menu with options to either to reformat the hard drive and relaod the operating system from the restore CD (or something like that, I am trying to recall from memory) or to display a list of utilities. If I select to show the utilities, it will show another menu with three options- show system information, show diagnostic utilities, or create a floppy disk to restore access to the diagnostic utilities. Most of the time, selecting to show the diagnostic utilities (2nd option) will cause a reboot. Other times I have been able to access the utilities and run them... alhtough haven't run all of them. I can also access the command line from these utilities, when I am able to load them. Tried running scandisk from here- if I run the scan disk on the C: drive (the IBM service partition) everything is fine. If I run it on the D: drive (the IBM_Preinstalled partition, which would be the C: drive on a normal boot and contains the Win Me install), the system reboots after scandisk runs for a few seconds. If I run scanreg /fix from the D: drive (the one that has Win Me installed) it will say that it couldn't repair the registry and that I should try deleting some files to free up space on the disk. If I run scanreg /restore, it says there is nothing to restore from.
Anyway, it seems exactly what is described in this threat, although I obviously haven't gotten as far as reformatting, swapping ram, or testing other hardware components. I also haven't had a chance to look at the capicitors around the processor as suggested on the thread linked to in the last post, but I honestly can't tell from that picture what I'm supposed to be looking for. I was surprised when I looked at the dates on this thread becasue they are just in the last week or so- and this happened to me today. The capacitor thread isn't that old either... and they're all Netvistas. Wonder if it's an issue with the Netvista motherboard. Anway, any help would be much appreciated and I will be following this thread with much interest. Thanks!