# Trying to identify certain board components



## punkymunk (Jul 5, 2017)

Hey everyone. I've come across 8 OLD circuit boards from an IBM server of the late 80's to early 90's. I was curious if anyone here could help me identify certain components on these boards. I included a picture but I haven't the foggiest idea as to what the silver looking square components are. The are several IC's and a couple EPROM-style chips. And I think the yellow boxes are tantalum capacitors... but not certain. Web searches on my end have turned up zilch except for a couple sites indicating board replacements but no real info on what they do and much less what the components are. Just wanting to properly segregate the parts into collection bins of same/similar for later processing after removing them is all. Thanks!

Oh and yes... I did try to check online for possible selling as whole values to collectors or anyone who happens to need them and there's no apparent market for these old boards so that's why I'm ready to proceed with depopulating them for PM recovery later on.


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## glorycloud (Jul 5, 2017)

It came out of an IBM System 36. That much I know. An ADP card.


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## cosmetal (Jul 5, 2017)

Personally, I haven’t the foggiest.

If you can’t get an answer on GRF, try Boardsort.com and ask *lostinlodos*. He/she is truly amazing when it comes to knowledge of electronic components and their functions.

James


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## shmandi (Jul 5, 2017)

Those yellow blocks could be tantalum (photo shows -++- marking on them), metal squares could be some hybrid circuits, the ones marked with black (resistors) are diodes.


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## mls26cwru (Jul 6, 2017)

the silver squares are IC chips of sorts... smaller ones are usually RAM chip modules, but larger ones could be CPU's are other types of chips. if you pop the top off, you will see a small silicon square inside with a bunch of leads and traces around the chip. they are kinda neat and i hear have some good PM's content.

The long yellow blocks are probably resistor arrays, while the small two lead blocks could be tantalum capacitors.



cosmetal said:


> Personally, I haven’t the foggiest.
> If you can’t get an answer on GRF, try Boardsort.com and ask *lostinlodos*. He/she is truly amazing when it comes to knowledge of electronic components and their functions.
> James



you put a lot of faith in a guy that spouts off a lot of BS... He has a decent scrapping knowledge, but is wrong/guessing on a whole bunch of stuff as well. Put more faith in the guys on this board here.


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## macfixer01 (Jul 6, 2017)

IBM is the only company I know of that makes some of it's chips packaged in aluminum shells like that. I've never heard of them having much of any PM's in them though? The light blue and white components are definitely resistor networks. The longer yellow packages apparently still only have 4 pins so I doubt they're resistor networks, maybe dual capacitors in one package? The best part is likely to be the pins inside those white plastic connectors on the board edges. Some IBM boards have a small gold (or gold alloy?) bead bonded to the surface of each pin. This has been mentioned by someone on the group before but it's been quite some time.

Macfixer01


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## Topher_osAUrus (Jul 6, 2017)

macfixer01 said:


> ... Some IBM boards have a small gold (or gold alloy?) bead bonded to the surface of each pin. This has been mentioned by someone on the group before but it's been quite some time.
> 
> Macfixer01



GSP mentions the little karat "pads" on some pins, in his book.
Page 17, Scrap type 23, bullet 2.


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## snoman701 (Jul 9, 2017)

IBM Solid Logic Technology Chips. on edit...per the board, not much in terms of PM content. Some PGM, some Ag

The white connectors at each end have a pad of >10k gold that is spot welded to a BeCu spring contact. The white plastic covers come off easy, then I remove the contacts with a pair of needle nose pliers.


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