Tyan 760MP - VERY strange problem!!!!!

[mgravy]

o.k. - I have never been so completely stumped and frustrated with anything, ever!!

I have had a Tyan 2462UNG AMD motherboard setup and running for about a year (dual 1.5 MHz processors). For some reason, the PS2 on the motherboard that the keyboard plugs into never worked, so I always used the USB connector from my MS Natural Keyboard, and this worked fine for almost a year. The keyboard issue had always stumped me, but I assumed that when I installed the mobo I accidentally shorted some connection on a standoff. I have tried several other PS2 keyboards that I knew worked from other machines, but I still had no success when attaching to my Tyan board. I can't access the BIOS by pressing F2 because the USB drivers hadn't loaded prior to windows loading. If I ever needed to re-install windows, I knew I would be in screwed, because I couldn't alter the boot sequence from the CD-ROM to the hard drive.

One other interesting note is that if I hooked up my keyboard using the PS2, I would not receive a "Keyboard error" during the boot-up. If I unplugged the keyboard all-together I would receive a "Keyboard error".

Anyway, a couple of weeks ago, I started getting hard crashes (BSOD) about once a day, so I thought that maybe I should try do a fresh install of Windows 2000. Of course, I wasn't able to access the BIOS to change the boot sequence so I figured I was definately screwed. Being that I had invested in several SCSI HD's, dual proc's, and the NMB power supply, I just decied to dump another $400 on the same mobo and do it over again.

So, I just received the new mobo Fed Ex, hooked it up, and went throught the boot up. I was relieved that I could access the BIOS with the keyboard using the PS2! I hooked up one SCSI HD and one SCSI CD-ROM and installed windows. No problems! Then, I went about hooking up another 2 SCSI HD's and another CD-RW. Now, when I boot-up I can't access the BIOS !!! Once windows loads up, I can use the keyboard through the USB port just like before! So, I started back from scratch with one hard drive and one CD-ROM, one floppy, etc. and I still cannot use keyboard via the PS2!!!!

What could be the problem?!?!?! I am about to have nervous breakdown!!!

 

[mechBgon]

What is your power supply's brand and model? The fact that it conks out when you add more electrical load is making me suspicious of your PSU's manhood, if you will

For a dual-AMD system with valuable SCSI equipment, I would throw in the best darn PSU I could lay hands on. Since the board doesn't use a standard ATX connector, this recommended-PSU list may help if you're not already familiar with it. I've checked out the specs on some of those, and the Delta is extremely potent if you can find a source for it (I haven't been able to). Here's another reputable unit with gobs of amperage, built for your board: Zippy

 

[mgravy]

I'm using the NMB 460w that was initially recommended for the Tyan 2462.

 

[mgravy]

This is interesting, I returned the board, received a new board and the PS2 connection on the Keyboard does not function. I am running the system bare bones with almost no load!

Question: I have a digital doc5 hooked up to the system and the voltage readouts seem to be steady. It reads +5.18v & +12.49v with only about 3 hundreths variation either way, that I have noticed. Is this an accurate measurement of the stability of my power supply or is this relatively meaningless??

Either way, I guess I'll ditch the NMB and get the Zippy. This just keeps getting more painfull on the wallet!!!