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M921 motherboard for 486 no POST. Anything to do before I toss it?

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First post, by GeorgeMan

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I just tested a PC Chips M921 v1.1A mobo, UMC chipset with onboard IDE/floppy and PCI, with an AMD 486DX4-100, an S3 Trio64V+ 1MB PCI and 2x16MB EDO Ram and a new CR2032 battery. Eveything else is tested and works.

When I power it up, the keyboard lights blink for a second and nothing else happens. Tried configuration for AMD 486DX2/4, enhanced 486DX4 and Intel 486DX, FSB 25/33/40MHz and 3.3/4.0v CPU voltage. Nothing changes. Speaker doesn't beep at all, I only get the blinking.

The board itself is in very good condition, it just had some bent headers and 1-2 very small minor scratches.
What else may I try to bring it back to life?

I upload the manual and here is a photo of the mobo:
th_IMG_20130909_025429_zpsc2e43ccb.jpg

Alternative manual source: http://motherboards.mbarron.net/models/486pci/m921.htm

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Reply 2 of 6, by Old Thrashbarg

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You'd think it would beep if it was just a memory problem. Still, I guess it's worth a shot.

If that is unsuccessful, and you don't mind a bit of tedious work, I'd take a close look at the chipset... I've had several boards where the big QFP chips had some legs broken loose from the solder pads. I dunno if they got banged up in storage, or if the board was flexed enough to pop 'em loose, or what. In any case, the boards were non-responsive just like yours, but I was able to resurrect most of them after finding the broken joints and resoldering them. It's not something you can really see with the naked eye... you need a magnifying glass and a needle (or small screwdriver or whatever), and gently prod at the legs to see if any of them move.

Reply 4 of 6, by GeorgeMan

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The link on the 1st post states that it supports EDO, so do some statements in old threads here about this UMC chipset.
But unfortunately I don't have FPM or other memory sticks, only these 🙁 So I guess I'm stuck for good.

I can also confirm that all legs are soldered properly. There is a scratch on 3-4 pins of one chip but they are just a little bent, not touching one another or anything else.

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Reply 5 of 6, by kixs

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vetz wrote:

Try some other memory sticks. I'm not sure this board supports EDO btw, may need FPM.

My thoughts exactly. I tested quite some 486 boards and to my surprise none supported EDO ram.

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Reply 6 of 6, by GeorgeMan

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Alrighty then!
Will try again when I have the luck to obtain some FPM ram...

Anyone else to confirm that no 486 mobo supports EDO?

Oh and something that seems important: When I fired the system up, the CPU didn't even warm up a bit. I didn't install a cooler for the tests and tried leaving in on for 1-2 minutes, but even then it wasn't warm.
May this mean something?

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