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Generic 486 motherboard, not sure of brand

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First post, by snorg

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Anyone have any idea what brand motherboard this might be? I can't see anything other than the BIOS and chipset that has any discernible markings. The chipset is SIS and I can't really make out the BIOS. Might be AMI/Award (was Award a BIOS type? Can't recall for sure).

Board had no cache but was a good deal and was listed as a working pull. There is also a "green PC" sticker on it, not sure what that's about.
Haven't booted it up yet because I don't have a test bed set up.

Reply 1 of 4, by NJRoadfan

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Its a Soyo SY-25N. I should know, because I own one.

http://www.elhvb.com/mobokive/archive/Soyo/ma … 5m/25m-mu20.pdf
http://stason.org/TULARC/pc/motherboards/S/SO … SY-25M-N-P.html

Its kinda lame board since it lacks the 3.3V VRM (only the SY-25P has it installed). I am very curious as to what revision BIOS it has. I really want a LBA compatible version (dated 7/25/94 or later). I know it exists as I've seen boards with it installed.

Reply 2 of 4, by snorg

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Ok, cool, good to know what it is. Both manuals you posted have a section for setting jumpers for 3.3 volt cpus. What do you mean by it not having a 3.3 volt vrm? Is that an optional component, or something that makes 3.3 volt operation more stable? I think (if I remember correctly) it stands for voltage regulator (not sure on the last one).

Reply 3 of 4, by NJRoadfan

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The board was sold in three versions. The "M" and "N" versions lack the 3.3v VRM, while the "P" version has it.

Reply 4 of 4, by snorg

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Well fortunately I have a 5 volt cpu I can put in there. So not a huge loss.

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