Strange voltages on P2B-S \ VOGONS

Strange voltages on P2B-S

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First post, by Mamba

Posted on 2021-10-22, 18:41

Mamba Offline

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Hello all,
The title speaks for itself.
I found a p2b-s with a p3 800/256/100 on it.
It seems to work properly, I updated the bios and tried all cpus I had (all 100Mhz FSB except for a Tualatin with modified slotket).

All CPUs make the board start, but the voltages are a bit strange -5V in special that is “0”!
See attachment.

Now, the PSU is a very solid Antec HCG that I use for several retro setups without any problem, even socket 7 or dual S370 / slot-1.

Any idea?

Reply 1 of 4, by Paadam

Posted on 2021-10-22, 20:36

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Nothing is wrong, just the PSU is too new to output -5v and it only matters to few ISA cards.

Many 3Dfx and Pentium III-S stuff.
My amibay FS thread: www.amibay.com/showthread.php?88030-Man ... -370-dual)

Reply 2 of 4, by Mamba

Posted on 2021-10-24, 15:59

Mamba Offline

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I expected something like that but honestly not to that extent.
I had not such voltage error with the p2b-DS…

Are you sure?
I just do not want to fry this nice motherboard.

Reply 3 of 4, by BitWrangler

Posted on 2021-10-24, 16:16

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I see no -5V here https://www.antec.com/product/power/images/hc … ld750_pdt09.png

See if the field will modify to ignore if it's bleeping at you on boot or something.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 4 of 4, by TheMobRules

Posted on 2021-10-24, 19:31

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BIOS voltage readings are not reliable, especially on a board of that era. Just use a multimeter directly on the PSU connectors, it will be far more accurate.

Regarding the -5V it's as others have said, it's not there anymore on PSUs since the mid 00's, nothing to worry about and it won't fry anything. Just ignore the error and don't worry about it.

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