Soyo SY-7VBA133 issues \ VOGONS

Soyo SY-7VBA133 issues

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First post, by vico

Posted on 2026-07-27, 17:34

vico Offline

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My motherboard doesn't usually boot when I turn it on. The power supply and CPU fans spin, but the POST doesn't happen.

However, if I remove the voltage jumper (VJ1) or change its position, the POST sometimes occurs.

I suspect it's an electrical problem, but I don't know which component could be failing.

I hope you can help me.

My specs:
Motherboard: SY-7VBA133
Processor: Intel SL4MF - 1.00GHz 133MHz 256K PGA370 Intel Pentium III
RAM: 256MB - 133MHz
Manual: https://theretroweb.com/motherboard/manual/m7 … 50376839785.pdf

Reply 1 of 14, by rasz_pl

Posted on 2026-07-27, 18:02

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capacitors wouldnt be a bad guess judging by 2001 vintage

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Reply 2 of 14, by Repo Man11

Posted on 2026-07-27, 18:12

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Just above the CPU I see three domed capacitors. My Soyo 7VMA-B had a few obliviously bad ones, I replaced all of them.

A lot of times when you first start out on a project you think, This is never going to be finished. But then it is, and you think, Wow, it wasn't even worth it. - Jack Handey

Reply 3 of 14, by TELVM

Posted on 2026-07-27, 18:14

TELVM Offline

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From a distance these three caps at least look like they're bulging:

file.php?mode=view&id=246399

Let the air flow!

Reply 4 of 14, by vico

Posted on 2026-07-30, 13:45

vico Offline

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Replacing the two capacitors to the right of the processor socket fixed the issue. Thanks to everyone for your help

Reply 5 of 14, by vico

Posted on 2026-08-02, 05:21

vico Offline

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The IDE2 is not working; it's not detecting my DVD optical drive. Could another capacitor be the cause?

Reply 6 of 14, by NeoG_

Posted on 2026-08-02, 07:11

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Have you checked if the DVD drive can be detected on IDE1?

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Reply 7 of 14, by vico

Posted on 2026-08-02, 14:43

vico Offline

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I did, IDE1 detects the DVD drive and the hard drive, IDE2 does not detect either of them

Reply 8 of 14, by vico

Posted on 2026-08-02, 21:00

vico Offline

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I've also noticed that the "Verifying DMI Pool Data..." message takes longer than it should

Reply 9 of 14, by TELVM

Posted on 2026-08-03, 06:44

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Is it possible that while recapping we scratched or solder-bridged some IDE2 related trace?

Let the air flow!

Reply 10 of 14, by rasz_pl

Posted on 2026-08-03, 12:09

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vico wrote on 2026-08-02, 21:00:

I've also noticed that the "Verifying DMI Pool Data..." message takes longer than it should

Verifying or updating? that would be worn out Bios EEPROM

Reply 11 of 14, by vico

Posted on 2026-08-03, 15:42

vico Offline

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rasz_pl wrote on 2026-08-03, 12:09:

vico wrote on 2026-08-02, 21:00:

I've also noticed that the "Verifying DMI Pool Data..." message takes longer than it should

Verifying or updating? that would be worn out Bios EEPROM

The cause was that the floppy disk drive was not properly connected.

Reply 12 of 14, by vico

Posted on 2026-08-03, 15:49

vico Offline

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TELVM wrote on 2026-08-03, 06:44:

Is it possible that while recapping we scratched or solder-bridged some IDE2 related trace?

I don't think so, but after replacing the 8 capacitors of 15000μ x 6.3v, IDE2 still doesn't work, so I had to struggle with the jumpers to connect both CD and hard drive to IDE1.

Reply 13 of 14, by vico

Posted on 2026-08-05, 17:37

vico Offline

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I'm having more problems with this motherboard; I can't install Windows XP. The installer takes me to a black screen after loading the drivers. Could these problems be due to electrical faults caused by other defective components?
By the way, the 1500µF capacitors I replaced were the ones I had available. I don't know if they're low ESR; could that cause problems?

Reply 14 of 14, by TELVM

Posted on 2026-08-05, 22:57

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Yep that might be the case if those you replaced were CPU VRM output caps, that really NEED to be low ESR.

Let the air flow!

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