Need Help!- DX-32 Motherboard Problem?

[KTD1]

Bridgeport 760/22
Serial# 760-22-270
MFG 06/96

Past couple of days I've been loosing video signal while running the machine.
If I re-booted the PC with Ctr+Alt+Del it would return.

Today when I started the machine I got an "A Drive failure". (Don't use it anyway)

While running the machine today I got a "Serious Error writing to C:" message that came up on the operation screen at the end of a program.

Reset the machine with the "Red Reset Button" and everything seemed ok.
I backed up all the files on the C:

Thinking it was likely a socket problem, I wiggled all the boards in the PC motherboard and made sure they were fully seated.

Now she's dead. No signs of life on monitor or keyboard.

PC Motherboard? I think the Siemens Drives are OK.

If so, what would I need to look for in a used 486 Motherboard?

[machintek]

1. Check logic power supply. Do you realize how old it is? Check the fan on it too.
2. Remove boards plugged into MOBO one at a time and clean the edge connector with a soft eraser. Plug back in.
3. Look at MOBO and find the CMOS battery. Measure voltage with power off. It is typically a stack up of 3 NI-CAD button cells welded together, covered with heat shrink tubing giving it a ribbed appearance, soldered to the MOBO near the keyboard plug. If there is any fuzziness in the vicinity of the battery, it may be leaking and eating up the MOBO. Also this may affect the CMOS settings resulting in a inability to see floppy and comm correctly to the C drive.
Good start.

George

[KTD1]

Originally Posted by machintek 1. Check logic power supply. Do you realize how old it is? Check the fan on it too. 2. Remove boards plugged into MOBO one at a time and clean the edge connector with a soft eraser. Plug back in. 3. Look at MOBO and find the CMOS battery. Measure voltage with power off. It is typically a stack up of 3 NI-CAD button cells welded together, covered with heat shrink tubing giving it a ribbed appearance, soldered to the MOBO near the keyboard plug. If there is any fuzziness in the vicinity of the battery, it may be leaking and eating up the MOBO. Also this may affect the CMOS settings resulting in a inability to see floppy and comm correctly to the C drive. Good start. George

Cleaned the boards and she’s up and running!
CMOS checking @ 1.3V Seems the previous owner had a low battery problem as well. They’ve already soldered leads to the board and a 3.6V lithium to the leads. I checked the local radio shack for another battery like that one but no luck.

I picked up a new coin battery holder and a new 2032 but before I solder it to the leads; do you think one coin battery is enough? There has to be a lot more milliamp hours in that AA sized lithium cell they installed.

Must I install the new battery with power on so as to prevent memory loss?

Your input to this forum is irreplaceable and most appreciated.
May I send a bottle of your favorite adult beverage?

[machintek]

Newer motherboards use a CR2032 to hold CMOS. On EBAY you can buy 20 of them for about 5 dollars from China including shipping. Current draw is minimal.
Glad you are running. I wish all problems were as easy.
A case of bear easily lasts a year. Recently my boys (both in college) have been helping me with those.
In other words, I appreciate the thought. Just help others. That is what makes a stronger and more knowledgeable community.

George