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First post, by tony359

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Hi all

I have installed an external battery on my SIS 486G motherboard and I noticed that after an extended period of time off, the BIOS would reset to default. I found a broken trace (the original battery had leaked and did some damage) and I fixed that. I have to wait till tomorrow to see if that fixed the issue.

I was wondering where is this voltage supposed to be going to prevent the settings from resetting? 'cause I can follow the battery voltage up to a small transistor but then it doesn't go anywhere else. Am I supposed to see that voltage somewhere on the BIOS chip?

Thank you!

My Youtube channel: https://www.youtube.com/@tony359

Reply 1 of 3, by tony359

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Fixing the broken traces seem to have fixed the problem. But I still would like to understand what is responsible for keeping the BIOS settings alive? It cannot be the BIOS chip itself?

My Youtube channel: https://www.youtube.com/@tony359

Reply 2 of 3, by Horun

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The CMOS is a ram chip built into the chipset or as a seperate part (like Dallas RTC) that holds the BIOS settings. The BIOS chip just holds the BIOS file.

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

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