Fighting a similar problem with an old SOYO beige mini-desktop box. If you have some spare 'known good' ram kicking around, try swapping out the ram, just for giggles. Unless you have a high end tester, it's almost impossible to isolate intermittent ram errors - and I can't count the number of times I've watched ram merrily pass any command line utility testing with flying colors - but after all else failed, swap out the ram and suddenly the crashes and rebooting went away. I've tried tackling it fromt he CMOS settings for the RAM but so far, that's never actually fixed an intermittent crash for me. Usually, if the problem is CMOS setting vs. hardware - it's repeatable, consistent, and when you find the culprit and make the necessary change, the difference is readily apparent. YMMV - anything you can imagine going wrong, has probably happened to somebody once, somewhere.
In this instance, I am refurbing five similar (but not quite identical) old PC's. While none of them are a thrill to operate, three cleaned up easily, one gave me intermittent fits, eventually swapped out the hard drive and did a clean install of W2k, and it seems to be okay now. I am not sure what the issue was with the hard drive - the drive passed the SeaTools tests with flying colors, but W2k repeatedly failed the drive while attempting to format it for a clean install. I gave up, swapped out the drive, and things went smoothly after that. Ran Ontrack Disk Manager (circa 2002 version) on the drive, it apparently passed the drive and formatted it. Haven't real world tested the drive yet - but it didn't 'act' like a bad drive. (Seagate Medalist - not one of my favorite things - but that's what came in the box.) Most of these units come up as being Celeron 500 Mhz w/128M ram, 10G hard drives.
The final system has a VIA 700 (100Mhz x 7) CPU, a Cyrix variant. It had Win 98 installed, kept crashing within a few moments of booting up. I swapped the ram, no change - so I decided to do a clean install of W2k Pro. Ugly, intermittent strangeness all the way. Turned off internal and external caching (can you hear the machine making dog noises from where you sit? Listen carefully, from here, the doggie noise feel deafening. BOW WOW WOW!!!! That got W2k to complete the initial pass, and get to the starting up Win 2000 screen. Where it fails... sometimes seems to get a little further than other times, but never gets to the point where it would ask me for the serial/key number. I used the same disk for the box with the questionable hard drive, so pretty sure the files are okay. (ISO burn from a MSDN image - legal software, I have two Microsoft 'partner' subscriptions that include 10 licenses for virtually every MS OS variant, for testing and in house purposes). Just to be sure, because the system had a dusty, kind of nasty old CD ROM drive in it, I swapped out the CD ROM drive for a never used 'new in a sealed box' 48x24x48 drive from a close out. The drive is a little faster, doesn't have dust bunnies floating around in it - but at the end of the day, a complete re-install takes me back to same point of almost there, but not quite. I'm back to hanging at the Microsoft Windows 2000 is starting screeen (which I currently feel is Microsoft's answer to the riddle, how do you keep an idiot in suspense?
The book indicates that these are SOYO LI-7000 LPX SYSTEMS - my understanding is that this one is a variant of the unit that came with the VIA CPU.
Near as I can tell, the motherboard is extremely similar to the SY-71WM/L V1.0 excepting the Award BIOS /chips are tweaked for VIA cpu compatibility. Same Whitney video, sigmatel sound, Realtek ethernet. same layout.
It's kind of perky, for as far as it manages to get to. It handles the early booting segment noticeably faster than the Celeron 500's. Since playing with the internal and external (L2) cache settings seems to make changes in where and how it fails, and it's always failing rather deep into the boot process - either hanging or going to black screen with a blinking underline in the extreme upper left corner, I'm concerned that I either have a bad motherboard (but don't think so because it ran DOS burn in testing just fine. I left some utilities running for hours that test the hard drive, the ram, etc and free-DOS runs great.
I'd love to hear any suggestions for troubleshooting - am afraid I may be running into a harware incompatibility.
Thanks for reading my saga....