Good evening....first post for me here. I've lurked for years if I ever needed a weird piece of information on some piece of weird old hardware....I have a pretty extensive retro collection, 31 years in the making....mostly 90's era gamers & workstations. Pretty much everything I've kept has been SMP of some form (old specialty of mine)....and here's one I'd love to add to the collection.....but it's not playing nice....so here we go. I am the owner of another known tech community, but nobody there really cares for this kind of stuff like it appears those around here do...Also I have been doing component-level service of computer gear all my career.... Anyway:

I was brought here (again) by this thread but opted not to wake it up since I didn't have anything to add to it: Supermicro P6DNE - Eaten by Varta´s barrel bomb -> back from the dead

Now for my pair pf P6DNE's. One had the same problem as above, Varta battery blew its load all over it and it was done....light brushing of the corrosion, and things were falling off it....it's a wallflower....

Now for the good one. Someone had the foresight decades ago to nip the battery off it; hence no corrosion damage to the PCB at all. There were a couple pins in the AFT end of the ISA slot right next to it that had the green crud on it.....but it was not a factor for anything.

This board will not POST. No beeps, no video, no nothing. I have played musical VRM's, CPU's, RAM, and GPU....I have quite a few P-Pro rigs in my collection, I had plenty to test with....no-go. CPU's and chips do warm up when power is applied. I am out of answers on this one....and that's saying a lot for me! I did find the manual with the jumper settings, and have verified them to all be correct.

Here's where one of the questions is still open in my head. This "3V SUPPLY" connector on the opposite side of the motherboard from the AT power connector.... I could not find any information on what this is for. Seeing some others that have done builds with these boards, they don't require a special PSU; any standard AT will work....but maybe I'm skipping a step somewhere?

I measured all 6 of these pins with the power off and on. From left to right in the pic, the first 3 (pins 1-2-3) are GND. Measuring OHM's from the last 3 (pins 4-5-6) to GND is ~200 ohm. With the board powered up, on pins 4-5-6 there is ~3.3v present. Does anyone know what that connector is for?

I'd sure like to figure this one out.... I don't think I could bring myself to send this to the e-waste shredder....I'd probably make a display piece out of it.....but I'd much rather see it work again. Thanks!!