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Half dead Asus A7V133 advice

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First post, by Minutemanqvs

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Hello,

I recently got an Asus A7V133 rev 1.05 "for parts", someone already stole the Northbridge cooler. I still wanted to see if it's somewhat alive so I cleaned it up. After checking that no traces seem broken and straightening all pins I could see I started it up with a POST analyzer, without CPU nor RAM:

https://youtube.com/shorts/NH6Kc2OIuDg

As you can hear, the voltage regulators (can't really tell which component on the vertical card) are really unhappy and the POST card displays nothing, as there is nothing to compute stuff. The yellow capacitors on the VRM seem bulged. After a while there is a beep indicating a missing CPU.

Good, next step is the same setup but with a Duron 700. This time the board starts up and displays codes. The VRM is now happy and doesn't make horrible sounds anymore:

https://youtube.com/shorts/9KVRM8gYdfE

All voltages on the POST card are there, the reset line is clear and it gets stuck at error C1 followed by dE. This seems to indicate missing memory (which works on other cards, I even tested it after this one to see if it died in the process). It also beeps about exactly that.

Now my issue is that I have tried with PC100 and PC133 memory in every of the 3 slots and it still hangs on the same error code. Does anyone have an idea on the next steps that could be done to debug that?

What I also did:
- Added a PCI Graphic card
- Reflashed the BIOS chip
- Configure the card to manual 1.6V, 100MHz FSB instead of JumperFree mode
- Check with a multimeter if there is VCC on the DIMM slots. There is, 3.45V as is the default on this board. If I set the jumper to 3.3V it follow stat.

Thanks for your advice!

Searching anything Nexgen, PM me if you have one. Also ATI Rage 128 PCI cards.

Reply 2 of 10, by Minutemanqvs

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cyclone3d wrote on 2026-02-10, 20:00:

Replace the bad caps and go from there.

This was my first idea, but I'm wondering if it should at least start "more" before being unstable. Meanwhile I maybe found a good culprit...

This is the back of the chipset from an image on https://theretroweb.com/motherboards/s/asus-a7v133-rev-1-05 :

retroweb.png

And this is mine...oh, 2 capacitors are missing. I can see they were ripped off :

mine.jpg

As the chipset is connected to memory I will probably start from there. Only problem, I don't know their value...I'll probably desolder one of the close ones and try to measure it. And then see if my dead Radeon 9800 has similar caps.

Searching anything Nexgen, PM me if you have one. Also ATI Rage 128 PCI cards.

Reply 3 of 10, by Minutemanqvs

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Ok so after replacing all the "big" capacitors around the VRM and RAM area and adding the 2 missing capacitors at the back of the board, it works again!

Searching anything Nexgen, PM me if you have one. Also ATI Rage 128 PCI cards.

Reply 4 of 10, by PC@LIVE

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Minutemanqvs wrote on 2026-02-20, 08:18:

Ok so after replacing all the "big" capacitors around the VRM and RAM area and adding the 2 missing capacitors at the back of the board, it works again!

I saw both of your YouTube videos, and I found them interesting, so you solved it by replacing and adding capacitors, and the A7V133 works! Congratulations 🍾

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Reply 5 of 10, by Crazyeights

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My A7V133 came with an active Northbridge cooler, the A7V does not. The fan gets noisy and fails. That is probably why yours is gone.

Reply 6 of 10, by Minutemanqvs

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So after just booting it, I ran some memtest86+ on it to test all memory slots individually. I also added a Northbridge heatsink. Now it's fully functional again!

IMG-3679.jpg
IMG-3677.jpg
IMG-3676.jpg

Searching anything Nexgen, PM me if you have one. Also ATI Rage 128 PCI cards.

Reply 7 of 10, by red-ray

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Minutemanqvs wrote on 2026-02-24, 18:03:

Now it's fully functional again! Searching anything Nexgen

Well done for getting it running. I have recently done similar with an ASUS A7V and am wondering, how different is the A7V-133? Once/if you have Windows installed please will you run my SIV utility and generate save files for me ?

I made a number of improvements to the ASUS A7V reporting so please use SIV V5.86 Beta-06 or later, the Unicode SIV32X for W2K and later or the ASCII SIV32L for W9x. To generate the save files do Menu->File->Save Local.

Do you have a Nexgen system?, if so I would love to know how SIV does on it.

Reply 8 of 10, by Minutemanqvs

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I can do that yes, just give me some time. Yes I have a NexGen PCI system with and without FPU (and if someone has more, this is really my sweet spot).

Searching anything Nexgen, PM me if you have one. Also ATI Rage 128 PCI cards.

Reply 9 of 10, by rasz_pl

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I frickin loved ASUS A7V series of boards. I ran A7V as my main machine for 7 years between 2001-2008. Moved from P2B with some overclocked Celeron coppermine to A7V with Duron 600@900, and the last A7V133 I sold was with XP 2400+

Minutemanqvs wrote on 2026-02-20, 08:18:

Ok so after replacing all the "big" capacitors around the VRM and RAM area

I havent seen anyone needing P2B or A7V capacitor replacement ever, are you sure those were bad?

Minutemanqvs wrote on 2026-02-20, 08:18:

and adding the 2 missing capacitors at the back of the board, it works again!

buzzing sound does make me think the problem was just those knocked off components

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Reply 10 of 10, by Minutemanqvs

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rasz_pl wrote on 2026-02-26, 00:18:
I frickin loved ASUS A7V series of boards. I ran A7V as my main machine for 7 years between 2001-2008. Moved from P2B with some […]
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I frickin loved ASUS A7V series of boards. I ran A7V as my main machine for 7 years between 2001-2008. Moved from P2B with some overclocked Celeron coppermine to A7V with Duron 600@900, and the last A7V133 I sold was with XP 2400+

Minutemanqvs wrote on 2026-02-20, 08:18:

Ok so after replacing all the "big" capacitors around the VRM and RAM area

I havent seen anyone needing P2B or A7V capacitor replacement ever, are you sure those were bad?

Minutemanqvs wrote on 2026-02-20, 08:18:

and adding the 2 missing capacitors at the back of the board, it works again!

buzzing sound does make me think the problem was just those knocked off components

You are mostly right. 2 of the yellow caps had a deviation of about 30% compared to their rating and one felt slightly bulged. But the other capacitors on the board were mostly in spec, but I didn't measure them all. After juste replacing the capacitors, the board still didn't boot but I had the components and now I'm sure.

But adding the 2 missing capacitors behind the chipset, and another one missing that was discovered later between the chipset/AGP port/memory and resoldering one that had a lose leg just next to it made the board really start.

Searching anything Nexgen, PM me if you have one. Also ATI Rage 128 PCI cards.

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