did i kill my 'puter

Those "integrated" CMOS devices were used on quite a few motherboards back in the 386/486 era. Cannot remember the manufacturere - but when the internal battery died you were cooked. I believe it was Dallas Semi. Some could be taken apart and a new battery soldered in. Sometimes you could cut the top off and solder wires to the 2 up-bent pins and connect a standard c-mos battery, and some guys just replaced the dallas with generic RTC chip -and an external battery.

Pain in the ARSE, for sure.

Most I saw were not even potted - just built into a glued or welded plastic box.

Reply to
clare
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There is usually a Bio "clear" pair of terminals that if shorted, will wipe the bios settings and bring it back to factory default.

Ive never heard of shorting the socket working. Much for me to learn!

Gunner

The methodology of the left has always been:

  1. Lie
  2. Repeat the lie as many times as possible
  3. Have as many people repeat the lie as often as possible
  4. Eventually, the uninformed believe the lie
  5. The lie will then be made into some form oflaw
  6. Then everyone must conform to the lie
Reply to
Gunner

Hang tough, and do what you can. We will be waiting for your return.

Gunner

The methodology of the left has always been:

  1. Lie
  2. Repeat the lie as many times as possible
  3. Have as many people repeat the lie as often as possible
  4. Eventually, the uninformed believe the lie
  5. The lie will then be made into some form oflaw
  6. Then everyone must conform to the lie
Reply to
Gunner

Too bad the PC based machine tools I work on..use an XT power supply.

Bummer

Gunner

The methodology of the left has always been:

  1. Lie
  2. Repeat the lie as many times as possible
  3. Have as many people repeat the lie as often as possible
  4. Eventually, the uninformed believe the lie
  5. The lie will then be made into some form oflaw
  6. Then everyone must conform to the lie
Reply to
Gunner

You are lucky The XT type supplies were a LOT more robust than the ATX (and you CAN convert an ATX power supply to run an XT motherboard)

Reply to
clare

What?..one needs a pin removal tool and?

I can find new 300 watt power supplies but they are getting harder to find.

Gunner

The methodology of the left has always been:

  1. Lie
  2. Repeat the lie as many times as possible
  3. Have as many people repeat the lie as often as possible
  4. Eventually, the uninformed believe the lie
  5. The lie will then be made into some form oflaw
  6. Then everyone must conform to the lie
Reply to
Gunner

Nope. I've personally seen it on $$$ equipment with top quality gold plated connectors. Reseat those connectors a few times and the problem goes away.

Reply to
Pete C.

Sometimes it's a cold solder joint somewhere that starts working again when the board is flexed and the oxidation is temporarily wiped. Chances are it will come back in either case.

Best regards, Spehro Pefhany

Reply to
Spehro Pefhany

Yes, I have experienced that too, especially with memory cards. I rub a piece of regular copy paper on the card contacts, it acts like like very fine sandpaper.

I think though what really happens is the oxide is on the contacts in the socket not on the gold card edge, but it works.

MikeB

Reply to
BQ340

It never has in my experience. The last one was some equipment that was unpowered for about a year and a half, lack of power seems to aggravate the issue. The equipment was having odd issues when powered up again, I powered down, reseated everything a few times and the problem went away. The problem never reappeared in the next four years the equipment was running.

Reply to
Pete C.

Exercising sockets is a valuable technique.

That's called burnishing the contacts, another valuable technique.

Gold isn't immune to oxidization (it forms an oxygen monolayer spontaneously), but the film is thin and it doesn't grow.

Tin also oxidizes, but a thin layer of tin oxide is conductive (it's indium/tin oxide that makes the transparent electrical connections for your LCD display).

Most important, is that a speck of dust or a film of oil or moisture can be submicroscopic and still impede the low voltage connections in a computer. So, disturbing the surface by mechanical wiping (like, when you loosen and reseat a memory module) fixes that entire class of problem.

Reply to
whit3rd

submicroscopic

I remembered this problem when a friend complained that the Cal Controls controller on her glass furnace was giving thermocouple failure faults. Various people had said to buy a new controller but as I have a Cal controller I was aware that the guts of the controller can be prised out of the panel mount enclosure, I presume to allow easy replacement when banks of them are fitted such as in plastic extruder lines. As I had mine apart to fit a comms module I was aware the PCB contacts were just tinned and might suffer this problem possibly causing issues with low level signals such as the thermocouple. I made a small pry bar to get the guts out and re-inserted it a couple of times and the problem went away. I've had the same happen on my controller more recently and removing and refitting it cured the fault.

Reply to
David Billington

I have a nice 5-channel thermocouple temperature display in the kitchen that I bought real cheap, and then found that it intermittently went haywire until firmly rapped. Un- and re-plugging everything has fixed it. The culprit was likely a socketed 40-pin IC.

formatting link

Now I can tell that a cooking pot on the woodstove downstairs has reached boiling before I smell it burning.

Reply to
Jim Wilkins

Hmm ... if it was something made after the ROHS requirement came in, and if the connectors were plated with pure tin to match the requirements, the pure tin grows conductive whiskers -- quickly or over long periods of time. Whiskers across pins in active equipment may be vaporized, while those across unpowered equipment will just stay there until it is powered on. If multiple whiskers bridge a given connection, there may not be sufficient current to blow the whiskers away.

But yes, oxidiation in connectors -- sitting idle or in frequent use -- can be a problem. My most frequent experience with that was the motherboard of the SWTP 6800 home computer kit. The bus connectors were each a row of fifty pins sticking up, and Molex connectors which slide over those. About once a year I would have to open it up and pull each board off and slide it on a few times to clean the oxide. A real pain, but at least I knew how to fix it. :-)

Good Luck, DoN.

Reply to
DoN. Nichols

I thought bad connections had bitten me this afternoon. I installed a new 2G RAM stick, booted, and got a message that memory had changed, ending with "To resolve this issue, try to reseat the memory".

Two or three long minutes later a prompt to hit F5 to run the boot rom diagnostics appeared. It passed just fine and then opened Windows properly.

Reply to
Jim Wilkins

Of course it changed. You *added* memory -- or replaced a failed unit (you didn't say which). It apparently does not know the difference between an increase in avaiable memory and a decrease. (Perhaps this is a side-effect of Windows being designed to consider any change a sign of possibly being moved to a new computer?)

Likely just compla Keyboard missing. Hit F1 to continue.

(and exactly how you were supposed to hit F1 when the keyboard was missing was not explained. :-)

Enjoy, DoN.

Reply to
DoN. Nichols

I work on them every day - and other than add-on cards I have NOT seen a single one in the last 8 or more years.

Reply to
clare

Now THAT I have seen.

Reply to
clare

If it was left sitting in a cool damp corrosive atmosphere I can see it. On a machine in relatively normal use it is NOT an issue any more

- although it definitely was a common failure a decade or more ago. Might be a problem on cheap crap machines - but I have not had the problen even on Dell - or Compaq/HP.

Reply to
clare

There was a product made for that - can't remember but I think it was de-ox-it. Put it on at assembly and NEVER have the problem. The concentrate was over $30 an ounce over 20 years ago - but you mixed it about 6:1 with ethanol and it went a LONG way.

Reply to
clare

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