Thanks for the info everyone. The CPU boards I have, and the one in rbrooks715's link, are of the dual 400MHz variety. They're the cheapest (then and now) and most common. At this point they're worth more for scrap than for a replacement part, unless you need one for a live environment. I've seen them before on
eBay for $5.00 each, NIB, and they never sold.
Bear, the "3000" is the Origin series (3rd generation). 3800 means it's a 5 or more rack system. The 3200 was a single rack, 3400 dual rack, etc. They all have the same parts, just different quantities of each, depending upon how many millions you had available to spend.
I've also updated the top.jpg and bottom.jpg pictures to better and higher resolution ones.
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