weedeewee wrote on 2021-05-14, 22:07:

PC@LIVE wrote on 2021-05-14, 21:27:

Before the block at post 41 and the continuous beeps, always make the long beep and the two short beeps, even with the POST CARD in the ISA slot.

Video adapter error. did you by chance leave the vga card out of the computer on that attempt ?

No the card is inserted in the slot, but it is as if it were not recognized, now I don't know if this depends on the + 3.3V (led off).
I did some checks, to understand what the + 3.3V mosfet is, I think it is one of those under the CPU, I will have to measure the voltage of both on pins 1 and 3.
Currently the values ​​of the others are quite normal when compared with other slot1 motherboards.
Regarding the continuity with the pin of the power supply (orange wire) and the PCI slot, for the moment I cannot find it, I do not know I have tried some pins but if you can tell me where to look, I have tried n ° 14 and 21, and it seems there is no continuity.

canthearu wrote on 2021-05-15, 10:58:

Also try using contact cleaner in the slots.

Often these old boards have been sitting around for a long time, the slots sometimes stop making good contact with cards.

A bit of contact cleaning will help it along if this is the case.

It is a good idea, I will clean up both the AGP and the PCI, while slot1 should be ok, as the CPU seems to be working.

Looking at the manual about memory it says something about memory, but it doesn't specify which modules (and which models) are installable and work.
This is written, if maybe you can tell me which modules are good:

2.5 MEMORY CONFIGURATION
The DIMM types supported are EDO and SDRAM. This mainboard has three 168 pin DIMM
sockets that allow you to install system memory up to 768MB.

"SIS5600 chipset can only use either 3.3V EDO or 3.3V SDRAM, so we cannot mix EDO and
SDRAM at the same time."

In 100MHz system, SPD SDRAM and PC100 specification SDRAM is preferred.


Serial Presence Detect (SPD)
-Specification
-SDRAMS: SDRAM SPD specification Rev 1.1 or later

- SPD usage and VIA BX Pro/Pro Plus systems
-100MHz Systems:
-MUST use SPD method to detect/size memory.
-If BIOS detects non-SPD DIMMS (or SPD data is invalid) in a system, the BIOS
should "BEEP" and stop executing POST. -"depends on the factory BIOS setting"
- What happens if non-SPD DIMMS are used in 100MHz system:
-BIOS cannot verify if the DIMMS used, meet 100MHz requirement.
-Memory access without programming Buffer strengths FIRST, may return incorrect data
and/or damage the memory
-Incorrect Buffer strength programming for REG. SDRAM.
-CAS# Latency, RAS#-CAS# delay and RAS# Precharge bits will need to be
programmed to lowest performance values
-BIOS cannot distinguish between 2&4 bank 64MB SDRAMS.

PC@LIVE wrote on 2021-05-15, 16:00:

No the card is inserted in the slot, but it is as if it were not recognized, now I don't know if this depends on the + 3.3V (led […]
Show full quote

No the card is inserted in the slot, but it is as if it were not recognized, now I don't know if this depends on the + 3.3V (led off).
I did some checks, to understand what the + 3.3V mosfet is, I think it is one of those under the CPU, I will have to measure the voltage of both on pins 1 and 3.
Currently the values ​​of the others are quite normal when compared with other slot1 motherboards.
Regarding the continuity with the pin of the power supply (orange wire) and the PCI slot, for the moment I cannot find it, I do not know I have tried some pins but if you can tell me where to look, I have tried n ° 14 and 21, and it seems there is no continuity.

https://pinouts.ru/Slots/PCI_pinout.shtml All the ones marked with +3.3V

though mostly if one doesn't have any continuity, the others probably also won't have any continuity.
However this lacking the 3V3 on the pci bus , could be by design, or it could be a fault to find.

PC@LIVE wrote on 2021-05-15, 16:00:

weedeewee wrote on 2021-05-14, 22:07:

PC@LIVE wrote on 2021-05-14, 21:27:

Before the block at post 41 and the continuous beeps, always make the long beep and the two short beeps, even with the POST CARD in the ISA slot.

Video adapter error. did you by chance leave the vga card out of the computer on that attempt ?

No the card is inserted in the slot, but it is as if it were not recognized, now I don't know if this depends on the + 3.3V (led off).

Don't think ISA slot has 3.3V, so shouldn't bother the graphics card.

I did some checks, to understand what the + 3.3V mosfet is, I think it is one of those under the CPU, I will have to measure the voltage of both on pins 1 and 3.
Currently the values ​​of the others are quite normal when compared with other slot1 motherboards.
Regarding the continuity with the pin of the power supply (orange wire) and the PCI slot, for the moment I cannot find it, I do not know I have tried some pins but if you can tell me where to look, I have tried n ° 14 and 21, and it seems there is no continuity.

It looks like this board can be powered from either ATX or AT supplies, so it's possible it doesn't use the ATX 3.3V supply at all, and just generates it from either 12V or 5V. I've got a SlotA motherboard that uses the 12V supply to generate all 3.3V supplies, and the AGP 1.5V as well. So there may not be connectivity between the 3.3V pins on the PCI slot and the 3.3V ATX power connector.

I've marked where I think there should be 3.3V on the PCI connector (edited photo from Wikipedia, By I, Jonathan Zander, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5000215), easily countable from the key notch. You can check (with board off) the resistance between to see if they're connected together. If they are, you should be able to use them to find where the 3.3V FET is.

weedeewee wrote on 2021-05-15, 16:15:

https://pinouts.ru/Slots/PCI_pinout.shtml All the ones marked with +3.3V […]
Show full quote

PC@LIVE wrote on 2021-05-15, 16:00:

No the card is inserted in the slot, but it is as if it were not recognized, now I don't know if this depends on the + 3.3V (led […]
Show full quote

No the card is inserted in the slot, but it is as if it were not recognized, now I don't know if this depends on the + 3.3V (led off).
I did some checks, to understand what the + 3.3V mosfet is, I think it is one of those under the CPU, I will have to measure the voltage of both on pins 1 and 3.
Currently the values ​​of the others are quite normal when compared with other slot1 motherboards.
Regarding the continuity with the pin of the power supply (orange wire) and the PCI slot, for the moment I cannot find it, I do not know I have tried some pins but if you can tell me where to look, I have tried n ° 14 and 21, and it seems there is no continuity.

https://pinouts.ru/Slots/PCI_pinout.shtml All the ones marked with +3.3V

though mostly if one doesn't have any continuity, the others probably also won't have any continuity.
However this lacking the 3V3 on the pci bus , could be by design, or it could be a fault to find.

OK thanks I'll try and see if I find tension in those PINs.

snufkin wrote on 2021-05-15, 16:45:

Don't think ISA slot has 3.3V, so shouldn't bother the graphics card. […]
Show full quote

PC@LIVE wrote on 2021-05-15, 16:00:

weedeewee wrote on 2021-05-14, 22:07:

Video adapter error. did you by chance leave the vga card out of the computer on that attempt ?

No the card is inserted in the slot, but it is as if it were not recognized, now I don't know if this depends on the + 3.3V (led off).

Don't think ISA slot has 3.3V, so shouldn't bother the graphics card.

I did some checks, to understand what the + 3.3V mosfet is, I think it is one of those under the CPU, I will have to measure the voltage of both on pins 1 and 3.
Currently the values ​​of the others are quite normal when compared with other slot1 motherboards.
Regarding the continuity with the pin of the power supply (orange wire) and the PCI slot, for the moment I cannot find it, I do not know I have tried some pins but if you can tell me where to look, I have tried n ° 14 and 21, and it seems there is no continuity.

It looks like this board can be powered from either ATX or AT supplies, so it's possible it doesn't use the ATX 3.3V supply at all, and just generates it from either 12V or 5V. I've got a SlotA motherboard that uses the 12V supply to generate all 3.3V supplies, and the AGP 1.5V as well. So there may not be connectivity between the 3.3V pins on the PCI slot and the 3.3V ATX power connector.

I've marked where I think there should be 3.3V on the PCI connector (edited photo from Wikipedia, By I, Jonathan Zander, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5000215), easily countable from the key notch. You can check (with board off) the resistance between to see if they're connected together. If they are, you should be able to use them to find where the 3.3V FET is.

OK thanks to you too.
Yes, I know that there is no + 3.3V in the ISA slot, in fact I was looking for it in the PCI slot.
I will do the check you suggest and I hope it is very useful to me, it is possible that the board does the + 3.3V (from + 5V), but I think there should be a mosfet that provides this voltage, perhaps as I said it is one of the two under the CPU.
But maybe it's a RAM problem, bad contact, in this case cleaning could solve the problem.

Have you tried recapping the whole board? I've had the issue of no POST on a QDI Advance 9 mobo and it was due to the Licon caps it had which failed with no signs. A full recap of the board (anything 1000uF and higher) brought my QDI back to life and would sucssesfully POST every time.

PcBytes wrote on 2021-05-16, 10:30:

Have you tried recapping the whole board? I've had the issue of no POST on a QDI Advance 9 mobo and it was due to the Licon caps it had which failed with no signs. A full recap of the board (anything 1000uF and higher) brought my QDI back to life and would sucssesfully POST every time.

No the capacitors are the original ones, but as I said before, the board works (not well), while usually with the failed capacitors it does not start or has problems with something, here it seems that the only thing that does not work is the +3.3 V, for the moment I am looking for a fault on the + 3.3V line, from the post card I use the LED is off, this means that there is a short or no current.
Lacking the + 3.3V current, I think both PCI and AGP and RAM are not working, and this should be the reason for the beeps, after the BIOS probably freezes because it does not recognize the RAM.
In any case, thanks for the suggestion, I will check the capacitors to see if they are shorted (or faulty), those present are marked "NOVA", the capacity is 1000uF 6.3V and 470uF 16V, other smaller ones are 100uF 16V.

snufkin wrote on 2021-05-15, 16:45:

PC@LIVE wrote on 2021-05-15, 16:00:

weedeewee wrote on 2021-05-14, 22:07:

It looks like this board can be powered from either ATX or AT supplies, so it's possible it doesn't use the ATX 3.3V supply at all, and just generates it from either 12V or 5V. I've got a SlotA motherboard that uses the 12V supply to generate all 3.3V supplies, and the AGP 1.5V as well. So there may not be connectivity between the 3.3V pins on the PCI slot and the 3.3V ATX power connector.

I've marked where I think there should be 3.3V on the PCI connector (edited photo from Wikipedia, By I, Jonathan Zander, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5000215), easily countable from the key notch. You can check (with board off) the resistance between to see if they're connected together. If they are, you should be able to use them to find where the 3.3V FET is.

Following the PINs of the PCI slot image, I identified which ones are the power supply voltages.
I found direct connection between pin A2 and + 12V (yellow wire), so this is ok, direct connection also for PIN A5 A61 A62 B6 B61 and B62, these are connected directly to + 5V (red wire), while not there is direct connection for the PIN A21 A27 A33 A39 A45 (these are to each other) and the PIN A53 B25 B31 B36 B41 B43 B54 with the + 3.3V of the power supply (orange wire).
For the moment I have not had time to check exactly where they go, but it seems that they are not directly connected to the mosfets present in the motherboard, for the moment I have arrived here.
I was thinking of an extreme solution in case I can't find where they go, in practice I would solder a wire between the orange one of the + 3.3V of the power supply and one of the PINs of the PCI (eg PIN A21).
This should solve the PCI slot problem, but I don't know if it solves the RAM one, I will still try to locate the RAM PINs to see if they are powered or not.

PC@LIVE wrote on 2021-05-16, 19:19:

Following the PINs of the PCI slot image, I identified which ones are the power supply voltages. I found direct connection betwe […]
Show full quote

Following the PINs of the PCI slot image, I identified which ones are the power supply voltages.
I found direct connection between pin A2 and + 12V (yellow wire), so this is ok, direct connection also for PIN A5 A61 A62 B6 B61 and B62, these are connected directly to + 5V (red wire), while not there is direct connection for the PIN A21 A27 A33 A39 A45 (these are to each other) and the PIN A53 B25 B31 B36 B41 B43 B54 with the + 3.3V of the power supply (orange wire).
For the moment I have not had time to check exactly where they go, but it seems that they are not directly connected to the mosfets present in the motherboard, for the moment I have arrived here.
I was thinking of an extreme solution in case I can't find where they go, in practice I would solder a wire between the orange one of the + 3.3V of the power supply and one of the PINs of the PCI (eg PIN A21).
This should solve the PCI slot problem, but I don't know if it solves the RAM one, I will still try to locate the RAM PINs to see if they are powered or not.

https://pinouts.ru/Memory/DimmSdram168Unbuf_pinout.shtml

Meanwhile, if it is useful to report the voltages measured in the mosfets of the motherboard.
For the two under the CPU it was not possible to measure the voltage with the PC turned on, because PIN 1 and 3 are under the CPU and are not easily accessible.
I will still try to measure them from below the MB, but if these measurements are not needed, I avoid doing them.
There are six mosfets in total, I don't know exactly if they are mosfets or other, for convenience I call them mosfet, but you can tell me what exactly they are by seeing the acronyms, this could be useful to me.
I report the voltages maybe they are useful to someone, the pins I have numbered them 1 2 and 3 one is the left (seen from above) the two is the central and the three is the right.
The 0V one is connected directly to the black wire.
Q6 ST9845 B3015L (1) +6.31V (2) +1.84V (3) 0V

Q8 ST9845 B3015L (1) +5.65V (2) +4.99V (3) +1.89V

Q4 75307D (1) +7.83V (2) +5.01V (3) +3.47V

Q22 75307D (1) +6.60V (2) +5.03V (3) +3.30V

Q7 - Q8 LX8384 (2) +2.50V - (2) +1.48V

weedeewee wrote on 2021-05-16, 19:31:

PC@LIVE wrote on 2021-05-16, 19:19:

Following the PINs of the PCI slot image, I identified which ones are the power supply voltages. I found direct connection betwe […]
Show full quote

Following the PINs of the PCI slot image, I identified which ones are the power supply voltages.
I found direct connection between pin A2 and + 12V (yellow wire), so this is ok, direct connection also for PIN A5 A61 A62 B6 B61 and B62, these are connected directly to + 5V (red wire), while not there is direct connection for the PIN A21 A27 A33 A39 A45 (these are to each other) and the PIN A53 B25 B31 B36 B41 B43 B54 with the + 3.3V of the power supply (orange wire).
For the moment I have not had time to check exactly where they go, but it seems that they are not directly connected to the mosfets present in the motherboard, for the moment I have arrived here.
I was thinking of an extreme solution in case I can't find where they go, in practice I would solder a wire between the orange one of the + 3.3V of the power supply and one of the PINs of the PCI (eg PIN A21).
This should solve the PCI slot problem, but I don't know if it solves the RAM one, I will still try to locate the RAM PINs to see if they are powered or not.

https://pinouts.ru/Memory/DimmSdram168Unbuf_pinout.shtml

OK thank you very much.
I will check this link and then check in the MB if I find connection to the mosfet, or to the + 3.3V PIN of the PCI.
I think that if there is no current in the RAM, the PC can hardly read them.
Here too, in an extreme case, the bridge between the orange wire and the + 3.3V PIN could be made, but it would be preferable to find the fault and fix it without having to resort to wires soldered on the back.

PC@LIVE wrote on 2021-05-16, 19:37:

Here too, in an extreme case, the bridge between the orange wire and the + 3.3V PIN could be made, but it would be preferable to find the fault and fix it without having to resort to wires soldered on the back.

agreed.

PC@LIVE wrote on 2021-05-16, 19:19:

while not there is direct connection for the PIN A21 A27 A33 A39 A45 (these are to each other) and the PIN A53 B25 B31 B36 B41 B43 B54 with the + 3.3V of the power supply (orange wire).

Well that's odd. Those are all 3.3V pins, but half not connected. I guess the NC ones goes to whichever FET supplies 3.3V when using an AT PSU? And it's possible the test card is only connected to one of those pins, which might explain why there's no light. I'd assume the PSU would shut down if there was a short, so can you measure the voltage on pin A53 with an ATX supply attached just to check whether there is 3.3V on it (you've measured a direct connection, so there pretty much must be).

I've got the same card, just slightly smaller main chip, and the 3v3 comes from only one pin A21

snufkin wrote on 2021-05-16, 20:00:

PC@LIVE wrote on 2021-05-16, 19:19:

while not there is direct connection for the PIN A21 A27 A33 A39 A45 (these are to each other) and the PIN A53 B25 B31 B36 B41 B43 B54 with the + 3.3V of the power supply (orange wire).

Well that's odd. Those are all 3.3V pins, but half not connected. I guess the NC ones goes to whichever FET supplies 3.3V when using an AT PSU? And it's possible the test card is only connected to one of those pins, which might explain why there's no light. I'd assume the PSU would shut down if there was a short, so can you measure the voltage on pin A53 with an ATX supply attached just to check whether there is 3.3V on it (you've measured a direct connection, so there pretty much must be).

Thank you for your suggestion.
Maybe I haven't written correctly (translating), I haven't checked the PINs from A53 to B54 yet, to see where they go.
While the PIN A21 is connected to the others following (A27 A33 A39 A45), but they are not connected to the orange wire of the + 3.3V, and I cannot find direct connection to the mosfets.
At this moment I have identified the PINs of the RAMs where to measure the voltage of + 3.3V, I have to check if in one of the 17 total PINs there is a connection to the orange wire, or to the mosfets.
In fact, for the short, the power supply should switch off, so excluding the short there is only to find why the + 3.3V voltage is missing.
But I don't think it's missing only in the PIN where the + 3.3V LED is connected.

weedeewee wrote on 2021-05-16, 20:18:

I've got the same card, just slightly smaller main chip, and the 3v3 comes from only one pin A21

Thanks so much.
This could be very useful for me to focus my research.
I will check if the voltage is present in the PIN A21, but I believe it is not there, I will try to find what the PIN A21 is connected to (mosfet Q ??)

maybe check between pin 6 of sdram and pin A21 of pci to see if connected .

weedeewee wrote on 2021-05-16, 20:31:

maybe check between pin 6 of sdram and pin A21 of pci to see if connected .

Ok I checked.
From a quick check the PIN A21 of the PCI and the PIN6 of the RAM are not connected.
But the PINs are not very accessible, I'll do another check from the back of the motherboard as soon as possible.
For the moment I have not done the PIN checks of the RAM, and I have to finish those of the PCI.

PC@LIVE wrote on 2021-05-16, 21:06:

Ok I checked. From a quick check the PIN A21 of the PCI and the PIN6 of the RAM are not connected. But the PINs are not very acc […]
Show full quote

weedeewee wrote on 2021-05-16, 20:31:

maybe check between pin 6 of sdram and pin A21 of pci to see if connected .

Ok I checked.
From a quick check the PIN A21 of the PCI and the PIN6 of the RAM are not connected.
But the PINs are not very accessible, I'll do another check from the back of the motherboard as soon as possible.
For the moment I have not done the PIN checks of the RAM, and I have to finish those of the PCI.

I don't know if it applies to this motherboard, but I know at least one (Abit KA7) where the RAM voltage supply is switched between the board's common 3.3V regulator (comes via the ATX 12V) and a separate 3.3V supply from the ATX 5VSB (for standby mode support). So for that board the RAM Vdd isn't directly connected to other 3.3V pins.

Still, all these 3.3V pins have to go somewhere.