ISA Memory hole?

Bad RAM ?

Mismatched modules ?

Can you boot and run stable?

I see lots of corrosion on the pins, clean them.

is ram being used for video or other bios shadowing?

rmay635703 wrote on 2020-07-23, 10:42:

ISA Memory hole? […]
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ISA Memory hole?

Bad RAM ?

Mismatched modules ?

Can you boot and run stable?

Dont know anything about the ISA memory hole, looks like a BIOS setting? Will take a look in the morning.
Have no idea if its bad, as i have not tested it yet, interestingly the second bank was full of 4mb 9 chip modules that the system does not recognise at all.
All modules are the identical as in the photo.

Miphee wrote on 2020-07-23, 11:57:

I see lots of corrosion on the pins, clean them.

I know what you mean in the photo, but doesnt look like corrosion, more like some sort of film, it cleaned off easy with an eraser anyway, made no difference.

Cobra42898 wrote on 2020-07-23, 12:22:

is ram being used for video or other bios shadowing?

all the shadow options are disabled, since the board has no battery, im assuming its booting up everytime with the default settings?

Check SOJ pins. Do you have another 4 MB module? Replace them 1 by 1.

Just tried those simms in my 386 machine and they show as 15424 KB which I guess is about right.

Oddly enough I tried some other simms that I know are 16 MB total on my 386 and they show up exactly as 16MB on the 486 board in question.
So my guess is that its a compatibility issue?

This board had 32MB installed originally by the looks too, it had installed 16MB of 9 chip simms on the second bank, but the board didn't even want to know about them, but they work fine on my 386.

Seems every motherboard displays a different size at times. Does enabling or disabling parity affect this?