In the Periodic Table of Videos episode Tin (new) - Periodic Table of Videos while talking about the role of the element tin in solder, Sir Martyn Poliakoff shows a large circuit board tiled with a variety of chip sizes and calls it a "a very old computer memory board" at about 02:39.

The chips are laid out in what I'd call "Manhattan-style" or Taxicab Geometry.

But to me it's more reminiscent of a complete computer. Does anyone recognize this board or at least something similar for comparison?

computer shown in Tin Periodic Table of Video

  • 2
    Doesn't like a memory board to me as well. There's just not enough uniform stuff to it. Without having the exact thing to compare, this is, however, impossible to answer. The horizontal ICs with stickers are obviously EPROMS, and there is apparently an oscillator on the top right. Nothing that I would search on a memory board.
    – tofro
    Aug 26 '18 at 7:07
  • @tofro agreed. I think it's that Manhattan layout that may have triggered his judgement.
    – uhoh
    Aug 26 '18 at 7:26
  • 2
    @uhoh I got memory card with such layout for an old XT in the past so layout alone is not important but I agree its not a memory board.... The decider for me was the connectors ...
    – Spektre
    Aug 26 '18 at 7:28

The lettering to the right of the CPU identifies the board:


It's a "SMD Control" board for a Nicolet Instruments FT-IR spectrometer, not a memory board (that's a separate board). More details here: https://se-source.com/nicolet-ftir-parts/

  • 5
    What clever thinking, actually look at the image ;-) This would then make perfect sense, considering it's a chemist sitting in a chemistry lab making chemistry videos.
    – uhoh
    Aug 26 '18 at 7:47

Sadly the image is not clear to see the chips markings :(

I do not recognize the board but the central DIL40? (I think AMD) chip looks like a CPU or MCU so it might be a whole computer or its just used to lower the IC count as a addressing mode selector/configurator or whatever.

The ICs with white label are most likely EEPROMs holding either firmware for the CPU/MCU or some custom stuff for the target computer (in case its a memory card).

The other 2 DIL40? ICs on the right can be anything (from a FDC/DMA/PIO/SIO or simple multiplexers/demultiplexer or whatever else).

The connectors are for quite a few wide cables. Based on the count of connectors and the pins count it looks more like for connecting peripherials then a master computer BUS connection which implies this is not a memory card. All the memory cards I saw got a connector that fits into single BUS slot on a PCB without cables (You do not want too long BUS connections due to noise and signal degradation).

Also the Reset? button on the right nearby the Crystal suggest this is a Computer board.

The 3 pin IC with heatsink on the top should be a Voltage regulator suggesting this has its own power supply whitch also suggest whole computer board.


So my educated guess is that you're right and this is a computer motherboard.

  • the ~12 chips/sockets at bottom left (partly hidden) might be some RAM. The two large DIPs on the right look like I/O controllers.
    – scruss
    Aug 26 '18 at 13:46

While traal's answer is definitive, there is a much quicker way to tell.

I'm old enough to recognize that style of circuit board, and simply looking at it tells me that it is not a memory board. The lack of an array of identical chips in a uniform rectangular grid is sure tipoff. Trust me, RAM arrays look like nothing else.

  • 2
    While "Trust me" is not the ideal kind of supporting material in a Stack Exchange answer, I'll take your word for it. (perhaps this one is better.)
    – uhoh
    Aug 26 '18 at 13:12

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