The reasons why that card does not POST can be many, for those who have some experience, know that there could be a HW problem and where to look for it, but before venturing into troubleshooting (possible?), it is necessary to make some attempts with the HW various, it is not certain that if you use working RAM, it will work on this MB, sometimes even the CMOS battery is flat, preventing booting, and you can still continue, ultimately the fault may not be there, and the card with the right combination of cards, it may start up and beep.

PC@LIVE wrote on 2024-06-22, 05:32:

The reasons why that card does not POST can be many, for those who have some experience, know that there could be a HW problem and where to look for it, but before venturing into troubleshooting (possible?), it is necessary to make some attempts with the HW various, it is not certain that if you use working RAM, it will work on this MB, sometimes even the CMOS battery is flat, preventing booting, and you can still continue, ultimately the fault may not be there, and the card with the right combination of cards, it may start up and beep.

Thank you! CMOS battery is fresh, I tried with 2x Katmai Slot 1 CPUs and 1x Coppermine Socket 370, with multiple GPU's both PCI and AGP, and with 4 different sticks of ram. All working hardware as tested.

berion wrote on 2024-06-22, 06:05:

PC@LIVE wrote on 2024-06-22, 05:32:

The reasons why that card does not POST can be many, for those who have some experience, know that there could be a HW problem and where to look for it, but before venturing into troubleshooting (possible?), it is necessary to make some attempts with the HW various, it is not certain that if you use working RAM, it will work on this MB, sometimes even the CMOS battery is flat, preventing booting, and you can still continue, ultimately the fault may not be there, and the card with the right combination of cards, it may start up and beep.

Thank you! CMOS battery is fresh, I tried with 2x Katmai Slot 1 CPUs and 1x Coppermine Socket 370, with multiple GPU's both PCI and AGP, and with 4 different sticks of ram. All working hardware as tested.

Ok so if you have an ISA video card, I would try that too, but I think you need to do some checks, if you have a tester measure the voltage on the mosfets, note everything down and write the values ​​found here.
Another thing you can do is put the POST card in the PCI, and see if it shows any code, if it does it will be easier to understand where the problem is.

PC@LIVE wrote on 2024-06-22, 06:29:

berion wrote on 2024-06-22, 06:05:

PC@LIVE wrote on 2024-06-22, 05:32:

The reasons why that card does not POST can be many, for those who have some experience, know that there could be a HW problem and where to look for it, but before venturing into troubleshooting (possible?), it is necessary to make some attempts with the HW various, it is not certain that if you use working RAM, it will work on this MB, sometimes even the CMOS battery is flat, preventing booting, and you can still continue, ultimately the fault may not be there, and the card with the right combination of cards, it may start up and beep.

Thank you! CMOS battery is fresh, I tried with 2x Katmai Slot 1 CPUs and 1x Coppermine Socket 370, with multiple GPU's both PCI and AGP, and with 4 different sticks of ram. All working hardware as tested.

Ok so if you have an ISA video card, I would try that too, but I think you need to do some checks, if you have a tester measure the voltage on the mosfets, note everything down and write the values ​​found here.
Another thing you can do is put the POST card in the PCI, and see if it shows any code, if it does it will be easier to understand where the problem is.

I’m a poor newbie with a multimeter so I’ll need google the deets but the pci slot shows this.

berion wrote on 2024-06-22, 14:43:

PC@LIVE wrote on 2024-06-22, 06:29:

berion wrote on 2024-06-22, 06:05:

Thank you! CMOS battery is fresh, I tried with 2x Katmai Slot 1 CPUs and 1x Coppermine Socket 370, with multiple GPU's both PCI and AGP, and with 4 different sticks of ram. All working hardware as tested.

Ok so if you have an ISA video card, I would try that too, but I think you need to do some checks, if you have a tester measure the voltage on the mosfets, note everything down and write the values ​​found here.
Another thing you can do is put the POST card in the PCI, and see if it shows any code, if it does it will be easier to understand where the problem is.

I’m a poor newbie with a multimeter so I’ll need google the deets but the pci slot shows this.

Hi, no problem, you don't have to be a technician to measure voltage with a tester.
First, I would download the manual, to see if any jumpers are misplaced or missing.
Afterwards if everything is ok, I would do a CMOS reset, I think there is a jumper near the battery, which needs to be moved and put back in place.
After the reset you need to check that the MB shows some code, by starting it you need to see if the three LEDs on the keyboard flash, and if you have a floppy disk drive, connect it, and see if it tries to read it.

I found a link where you can find everything you need:
https://theretroweb.com/motherboards/s/jetway-j-9bxan

Looking at the picture, I recommend you use a Celeron 370 Mendocino CPU, if it works with that, the card is ok.
Those CPUs have 128 KB L2 cache, and range from 300 to 533 MHz.
Does that MB have both Slot1 and socket 370? If yes, then both should not be used, unless it is specified in the manual that it can work with two CPUs.

PC@LIVE wrote on 2024-06-22, 15:25:

I found a link where you can find everything you need: https://theretroweb.com/motherboards/s/jetway-j-9bxan […]
Show full quote

I found a link where you can find everything you need:
https://theretroweb.com/motherboards/s/jetway-j-9bxan

Looking at the picture, I recommend you use a Celeron 370 Mendocino CPU, if it works with that, the card is ok.
Those CPUs have 128 KB L2 cache, and range from 300 to 533 MHz.
Does that MB have both Slot1 and socket 370? If yes, then both should not be used, unless it is specified in the manual that it can work with two CPUs.

Yep I mentioned that link in my original post. This board supports up to a Coppermine CPU and I tried it with 2 different Slot1 processors and another Socket 370 Coppermine. The board has a jumper to switch between the sockets.

PC@LIVE wrote on 2024-06-22, 15:14:

Hi, no problem, you don't have to be a technician to measure voltage with a tester. First, I would download the manual, to see i […]
Show full quote

berion wrote on 2024-06-22, 14:43:

PC@LIVE wrote on 2024-06-22, 06:29:

Ok so if you have an ISA video card, I would try that too, but I think you need to do some checks, if you have a tester measure the voltage on the mosfets, note everything down and write the values ​​found here.
Another thing you can do is put the POST card in the PCI, and see if it shows any code, if it does it will be easier to understand where the problem is.

I’m a poor newbie with a multimeter so I’ll need google the deets but the pci slot shows this.

Hi, no problem, you don't have to be a technician to measure voltage with a tester.
First, I would download the manual, to see if any jumpers are misplaced or missing.
Afterwards if everything is ok, I would do a CMOS reset, I think there is a jumper near the battery, which needs to be moved and put back in place.
After the reset you need to check that the MB shows some code, by starting it you need to see if the three LEDs on the keyboard flash, and if you have a floppy disk drive, connect it, and see if it tries to read it.

No read on the FDD. Keyboard lights flash when power on. CMOS reset. Jumpers are all in place. I think we’re looking at something hardware.
Another thing. When the board is bare as in no cpu, I can reset normally. When I have a CPU inserted, and I reset, the PSU shuts down and remains unresponsive until I unplug the 24pin and plug it back.

If you want to try to make some measurements, with the DC volt tester, the mosfets (or regulators?), are located near the inductors, they have 3 pins and two are soldered to the MB, the one in the middle is usually cut, but it is possible measure it at the top, that is, above the mosfet there is a metal part (soldered), that would be pin 2, the others 1 and 3.
Turn on the tester and connect the black probe to the black wire of the power supply, with the red probe measure on pins 1, 2 and 3, note the measurements and report them here.
Be careful not to touch anything else nearby, when you measure with MB turned on, naturally you have to add CPU and RAM, and if you want also video card.

PC@LIVE wrote on 2024-06-22, 17:00:

Turn on the tester and connect the black probe to the black wire of the power supply, with the red probe measure on pins 1, 2 and 3, note the measurements and report them here.

With the MB on and fans running?

PC@LIVE wrote on 2024-06-22, 17:00:

Be careful not to touch anything else nearby, when you measure with MB turned on, naturally you have to add CPU and RAM, and if you want also video card.

I watched some tutorial on Youtube and here's what I tested so far:

Both mosfets:
Regardless black or red probe on pin 2, other probe on pin 1 I get a buzz and an overload. other probe on pin 3 I get nothing.
Is that any help?

Additionally I assume these two coils are inductors and I’m getting continuity between them and ground.

berion wrote on 2024-06-22, 19:40:

PC@LIVE wrote on 2024-06-22, 17:00:

Turn on the tester and connect the black probe to the black wire of the power supply, with the red probe measure on pins 1, 2 and 3, note the measurements and report them here.

With the MB on and fans running?

Yes, the motherboard must have the minimum equipment to be able to boot, therefore keyboard CPU (including fan) and RAM, the rest can be added later.
Start the MB, the fans will have to spin, if they don't, it means that there is something wrong, then proceed with the voltage measurements.
From the values ​​found, it is easy to understand if something is not working, or if all the measures are fine.
However, if you found a Mendocino CPU, in my opinion you would have a better chance of booting, and above all the correct RAM should be used, in that case at least PC100, and not too high a capacity of MB, 32 or 64 MB are fine, use only one module.

berion wrote on 2024-06-22, 21:29:

Additionally I assume these two coils are inductors and I’m getting continuity between them and ground.

Yes, those are the inductors, and they must show continuity, but I would like you to measure the DC Volts, you can also make a measurement on the coils, but it is better if you measure on the mosfets circled in red.

berion wrote on 2024-06-22, 21:25:

I watched some tutorial on Youtube and here's what I tested so far: […]
Show full quote

PC@LIVE wrote on 2024-06-22, 17:00:

Be careful not to touch anything else nearby, when you measure with MB turned on, naturally you have to add CPU and RAM, and if you want also video card.

I watched some tutorial on Youtube and here's what I tested so far:

Both mosfets:
Regardless black or red probe on pin 2, other probe on pin 1 I get a buzz and an overload. other probe on pin 3 I get nothing.
Is that any help?

Honestly, I don't quite understand what measurements you did, but I advise you to do them with the PC turned off and disconnected.
However, if you want to make voltage measurements on the mosfets, the PC must be turned on and in working order, take the measurements, take notes, and then share them here.

PC@LIVE wrote on 2024-06-22, 21:43:

berion wrote on 2024-06-22, 21:25:

I watched some tutorial on Youtube and here's what I tested so far: […]
Show full quote

PC@LIVE wrote on 2024-06-22, 17:00:

Be careful not to touch anything else nearby, when you measure with MB turned on, naturally you have to add CPU and RAM, and if you want also video card.

I watched some tutorial on Youtube and here's what I tested so far:

Both mosfets:
Regardless black or red probe on pin 2, other probe on pin 1 I get a buzz and an overload. other probe on pin 3 I get nothing.
Is that any help?

Honestly, I don't quite understand what measurements you did, but I advise you to do them with the PC turned off and disconnected.
However, if you want to make voltage measurements on the mosfets, the PC must be turned on and in working order, take the measurements, take notes, and then share them here.

ok here we go, I hope I got this right.
CPU slot 1 in, pc100 128mb in
Fans on

MOSFET1 (bottom)
pin 1: 2V
pin2: 4.92v
pin3: 5v

MOSFET2 (top)
pin1 0.04 v
pin2 2v
pin3 5v

I think I got this right as I rechecked several times.

berion wrote on 2024-06-22, 22:47:

ok here we go, I hope I got this right. CPU slot 1 in, pc100 128mb in Fans on […]
Show full quote

PC@LIVE wrote on 2024-06-22, 21:43:

berion wrote on 2024-06-22, 21:25:

I watched some tutorial on Youtube and here's what I tested so far: […]
Show full quote

I watched some tutorial on Youtube and here's what I tested so far:

Both mosfets:
Regardless black or red probe on pin 2, other probe on pin 1 I get a buzz and an overload. other probe on pin 3 I get nothing.
Is that any help?

Honestly, I don't quite understand what measurements you did, but I advise you to do them with the PC turned off and disconnected.
However, if you want to make voltage measurements on the mosfets, the PC must be turned on and in working order, take the measurements, take notes, and then share them here.

ok here we go, I hope I got this right.
CPU slot 1 in, pc100 128mb in
Fans on

MOSFET1 (bottom)
pin 1: 2V
pin2: 4.92v
pin3: 5v

MOSFET2 (top)
pin1 0.04 v
pin2 2v
pin3 5v

I think I got this right as I rechecked several times.

So, since you use CPU Slot1, know that the contacts of slot1 tend to oxidize and may not make good contact, if so, you will not see any post code, socket 370 on the other hand, could be in excellent condition, I believe that if it works that, it is clear that the problem is in slot1.
Looking at the measured values, there doesn't seem to be anything strange, so at least those two seem to work.

Ok I'll buy a 100 MHz Coppermine as the one I tried before was a 133 Mhz 866.
We'll see what happens. Thank you for all your help and support.

PC@LIVE wrote on 2024-06-22, 23:21:

berion wrote on 2024-06-22, 22:47:

ok here we go, I hope I got this right. CPU slot 1 in, pc100 128mb in Fans on […]
Show full quote

PC@LIVE wrote on 2024-06-22, 21:43:

Honestly, I don't quite understand what measurements you did, but I advise you to do them with the PC turned off and disconnected.
However, if you want to make voltage measurements on the mosfets, the PC must be turned on and in working order, take the measurements, take notes, and then share them here.

ok here we go, I hope I got this right.
CPU slot 1 in, pc100 128mb in
Fans on

MOSFET1 (bottom)
pin 1: 2V
pin2: 4.92v
pin3: 5v

MOSFET2 (top)
pin1 0.04 v
pin2 2v
pin3 5v

I think I got this right as I rechecked several times.

So, since you use CPU Slot1, know that the contacts of slot1 tend to oxidize and may not make good contact, if so, you will not see any post code, socket 370 on the other hand, could be in excellent condition, I believe that if it works that, it is clear that the problem is in slot1.
Looking at the measured values, there doesn't seem to be anything strange, so at least those two seem to work.

My concern also is that not getting any codes on the POST card.