Unfortunately though I am making progress, I can't say I'm seeing results (yet). I received a Pentium Pro CPU (200MHz, 256kb) - it was cool to handle such a large processor. I have a TR3 system which when putting it together in ~December left quite an impression handling the CPU, yet the PPro almost seems larger and heavier still.
I thought I'd have to wait for RAM until I remembered I had bought this fully populated Compaq server RAM expansion board for cheap on eBay many years ago. It had been sitting wrapped in an antistatic bag all this time; I dug it out and lo and behold, no shortage of 168 pin EDO ECC FPM RAM! I borrowed four identical sticks from it...
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So, I populated the CPU board like so... ignoring heat sink for the moment since the case fan blows directly onto the processor when the installed.
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And flip the switch... and.... sigh. When powering the machine, little happens... no fan, occasional barely audible click of a relay from somewhere in the system, and a motherboard LED flashing every second. It's the exact same behavior you see on a Deskpro XL if you unplug the fan from the motherboard. So... hmm.
Potential problem areas:
1) CPU could be bad. I have no reason to think this... it looks relatively undamaged, top and bottom, with no bent pins. I really don't want to purchase another.
2) CPU board could be bad... I will unwrap the second one and give it a try. I double checked the SW2 and SW3 configurations per the quick reference guide - they are correct.
3) Could be the RAM I used is not 100% compatible but that should be easy to verify with a couple of other sticks. I am using 4 sticks of 228468-001 from that server RAM board, which appears to be a 32MB EDO ECC 60ns stick. Should be OK?
4) My hunch is that the XL requires the newer system/IO board to use the PPro cards. I wish someone had one of the newer systems & could verify. I do not see a path to sourcing the newer system board.
Finally, regarding the mysterious two connectors on the PPro board, I still don't know what they are, but I noticed Compaq's old memory upgrade reference has this cartoon drawing, almost suggesting a board should be in this location. Mystery!
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