The issue is located on the POWER ON circuit. Even without any card or cpu, the board should turn on. End it does not.
My guess is a dead SIO (super input/output chip). But I don't have a spare to try a swap.
The cap that was missing is located on the back of the board, were the socket it is. It was probably a decoupling cap and it's not impeding the board to power on if missing.
I think you'd get better help on Vogons. Go there and open a thread....
N²x²N
Senior Member
Last Activity: 04-02-2025, 02:24 PM
Joined: 04-02-2023
Location: Italy
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Never found it. Sorry for the bad news.
Still can't figure out why it won't power on....Leave a comment:
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Up again...Leave a comment:
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I repaired the board thanks to the schematics.
This reply comes in quite late but thanks a lot for the help.
Board works perfectly, old but fine!...Leave a comment:
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80286 motherboard - any model schematics
Hi!
I'm looking for any 80286 based motherboard schematics.
Thanks for any help!! -
Re: Pentium 2 and 3 Slot1 + K7 SlotA schematics
Found nothing.
Probably there are no schematics fro these.Leave a comment:
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Re: Pentium 2 and 3 Slot1 + K7 SlotA schematics
I meant the CPUs themselves, not the motherboards.
Unless it brings me there.
I'll check it later, thanks for the input!...Leave a comment:
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Pentium 2 and 3 Slot1 + K7 SlotA schematics
Hello!!
I was curious to know if they are available. I GG'd it but didn' find anything.
While I was storing some I checked others and they had missing caps and res (they were in the box). That was due to cards with no h/s hitting each other. Yes, I just piled them but wasn't a good idea
They all POST, but I don't know if stable (didn't bother benching them).
I stored them in an antistatic bag to avoid this in the future.
Thanks for any help!! -
Re: ASROCK K7VT4A PRO schematics (socket 462)
Up againLeave a comment:
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Re: ASROCK K7VT4A PRO schematics (socket 462)
Up again, maybe there is hope.
Leave a comment:
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FireGL V7300 7350 - repair
Hello!!
I already posted in the schematics section but no go. Old card and thus to be expected.
But I can try to ask here.
In the pic you can see two components, one is missing and one is damaged.
The damaged one the same as others that are already on the board:
K1N sot-23, guessing it's [url]https://pdf1.alldatasheet.net/datasheet-pdf/view-marking/1031870/DIODES/MMBT3904-7-F.html[/url]
The missing one is a capacitor, guessing it could be the same as some other around that area. Who knows for sure?
The...Last edited by N²x²N; 06-07-2023, 09:12 AM. -
Re: FireGL V7300 7350 - schematics
BumpLeave a comment:
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Re: FireGL V7300 7350 - schematics
Pic
I need to find C139....Leave a comment:
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FireGL V7300 7350 - schematics
Hello,
have this but a couple of components prevent me from even trying to power it up.
One is a K1N sot-23, guessing it's [url]https://pdf1.alldatasheet.net/datasheet-pdf/view-marking/1031870/DIODES/MMBT3904-7-F.html[/url]
The other one is a capacitor and good luck to myself finding the correct value.
Thanks for any help!https://Hello, <br /> <br /> have ...7-F.html[/url] -
Re: Asrock G41M-VS3 R2.0 - repair journey
No repair for this one.
I desoldered the southbridge and the shorts went away. A heatgun with preheat from bottom worked. It took like 5 minutes though, sounding like chip killer having to go up to 350°C to actually remove it.
A few pads came off but they were NC or GND. like 6/7 in all. Not bad for a first time.
It's not economical to replace it, let alone doing the job on the no-room placement of the chip.
Now it's a donor board for what's on it.
Really interested in knowing how it could have...Leave a comment:
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Re: ASROCK K7VT4A PRO repair
If it isn't another problem maybe it's the SIO.
Any ideas are welcome.Leave a comment:
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Re: ASROCK K7VT4A PRO schematics (socket 462)
Bump!
Leave a comment:
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Socket A schematics - any board with VIA chipset (KT400A if possible)
I can't find schematics for any socket A motherboard, probably my mistake in search terms.
I'm troubleshooting a KT400A based board and would like to try something but I have no schematics to at least give it an attempt.
Most important is the power on schematic.
We try until we throw the towel.
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Re: ASROCK K7VT4A PRO repair
3.5V is as expected, circuit is correctly outputting V.
It's 1.5V AGP, not 1.8. TypoLeave a comment:
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