The P2B is an old-school 440BX motherboard where everything still had to be configured with jumpers. Double-check to make sure that your CPU voltage/multiplier, AGP divider, and FSB jumpers are correctly set. Especially the FSB/AGP divider can result in a blank screen if your video card is the least bit sensitive...

p.s. There are physically compatible but otherwise incompatible SD-RAM DIMM-modules in existence that you could plug into the motherboard. If your DIMMs use the higher density memory chips, this can result in issues. For example, if you have a 256 MB DIMM which has memory chips on only one side of the module, you likely have an incompatible memory module.

If you 100% sure the power supply is working, you must consider these possibilities;

1. Bad mosfet.

2. Broken traces. You must check the traces that are connected to the power socket.

if the guy told you it was working, then it is probably some "component seating " problem ...

I would open the the case and gently reseat everything...
- remove the video card and other expansion cards, and reseat them
- remove the memory modules and reseat them
- remove the hard drive and cd-rom cables and re install them, both on the drive as well as on the motherboard

The mobo is receiving power so it is probably not a power supply issue .. the constant blinking tells the motherboard is not happy about something

if none of this works remove/disconnect everything not necessary for boot, like cd rom, floppy , sound cards, expension cards ... keyboard, mouse
leave only the video card
if there are more than 1 ram stick, remove and try only with one at a time (try to identify witch one is bank 0 and place it on bank 0
Try the sistem with another hard disk if you have... some motherboards will not boot with bad or absent hard disks

lastly try also removing the graphics card you can remove and see if you hear some error beeps

lastly lastly.. try to remove the cpu fan and the cpu from its socket and reseat those... you might need to buy a bit of thermal paste to apply and clean the old one ... so do this as last step.

GOOD LUCK !

I am 90% sure that computer is ok... its just some minor issue

dominusprog wrote on 2023-08-24, 11:26:

If you 100% sure the power supply is working, you must consider these possibilities;

1. Bad mosfet.

2. Broken traces. You must check the traces that are connected to the power socket.

My Pentium II computer with Abit BE6-II does something similar too. Does not want post picture. But i change videocards, than finally starts. Than pushing out-in ide cables, than will not start again. I do bios reset, battery remove, videocard remove, don’t start. I repeat everything than will start. And than starts every time until i do something inside. Now again don’t want to start. I maybe gonna change the whole motherboard. Or what can it be?

I already disassembled everything from the case, and put the motherboard alone to test..........but continues to not boot in any way, since the motherboard doesn't even spin up the CPU fan, i think something got short circuit...who knows.

Bummer, time to send it back 🙁 something got damaged during the shipment transport or maybe the seller lied. He didn't send any screenshot of the working PC after all

Atom Ant wrote on 2023-08-24, 18:21:

My Pentium II computer with Abit BE6-II does something similar too. Does not want post picture. But i change videocards, than finally starts. Than pushing out-in ide cables, than will not start again. I do bios reset, battery remove, videocard remove, don’t start. I repeat everything than will start. And than starts every time until i do something inside. Now again don’t want to start. I maybe gonna change the whole motherboard. Or what can it be?

I'd say 90% motherboard's fault yeah.

Nunoalex wrote on 2023-08-24, 18:14:

if the guy told you it was working, then it is probably some "component seating " problem ... […]
Show full quote

if the guy told you it was working, then it is probably some "component seating " problem ...

I would open the the case and gently reseat everything...
- remove the video card and other expansion cards, and reseat them
- remove the memory modules and reseat them
- remove the hard drive and cd-rom cables and re install them, both on the drive as well as on the motherboard

The mobo is receiving power so it is probably not a power supply issue .. the constant blinking tells the motherboard is not happy about something

if none of this works remove/disconnect everything not necessary for boot, like cd rom, floppy , sound cards, expension cards ... keyboard, mouse
leave only the video card
if there are more than 1 ram stick, remove and try only with one at a time (try to identify witch one is bank 0 and place it on bank 0
Try the sistem with another hard disk if you have... some motherboards will not boot with bad or absent hard disks

lastly try also removing the graphics card you can remove and see if you hear some error beeps

lastly lastly.. try to remove the cpu fan and the cpu from its socket and reseat those... you might need to buy a bit of thermal paste to apply and clean the old one ... so do this as last step.

None of these things have anything to do with the CPU fan not starting.

GOOD LUCK !

I am 90% sure that computer is ok... its just some minor issue

Being optimistic is a good thing but it seems that the glass is broken 🙁

Is there anything gets hot on the board (like bridges, big chips, mosfets), when it's connected to the power supply?
Do you have multimeter to test some voltages?

Zerthimon wrote on 2023-08-24, 19:42:

Is there anything gets hot on the board (like bridges, big chips, mosfets), when it's connected to the power supply?
Do you have multimeter to test some voltages?

Mmmh didnt' check this particular thing, i'll let you know

Some news, i let the motherboard on for some minutes....nothing gets warm......even slighty warm, CPU....southbridge, nortbridge, ram, video card......every chip stays cold.

- Yes i tried different PSUs
- Yes jumpers are fine
- Yes i did the tests with and without the coin cr2032 battery
- Yes i tried multiple RAMs modules + video cards both agp or pci

So the motherboard gets no power at all, ( but the power supply turns on anyway ), it's like the motherboard is stuck on suspension mode or something ( that's why the power LED is blinking i suppose ). I have no skills to repair the mobo, sadly i think it's time to toss that away

_StIwY_ wrote on 2023-08-25, 15:49:

Some news, i let the motherboard on for some minutes....nothing gets warm......even slighty warm, CPU....southbridge, nortbridg […]
Show full quote

Some news, i let the motherboard on for some minutes....nothing gets warm......even slighty warm, CPU....southbridge, nortbridge, ram, video card......every chip stays cold.

- Yes i tried different PSUs
- Yes jumpers are fine
- Yes i did the tests with and without the coin cr2032 battery
- Yes i tried multiple RAMs modules + video cards both agp or pci

So the motherboard gets no power at all, ( but the power supply turns on anyway ), it's like the motherboard is stuck on suspension mode or something ( that's why the power LED is blinking i suppose ). I have no skills to repair the mobo, sadly i think it's time to toss that away

Sad to hear, but like I mentioned before, the MOSFETs are the main suspect.

dominusprog wrote on 2023-08-25, 17:14:

_StIwY_ wrote on 2023-08-25, 15:49:

Some news, i let the motherboard on for some minutes....nothing gets warm......even slighty warm, CPU....southbridge, nortbridg […]
Show full quote

Some news, i let the motherboard on for some minutes....nothing gets warm......even slighty warm, CPU....southbridge, nortbridge, ram, video card......every chip stays cold.

- Yes i tried different PSUs
- Yes jumpers are fine
- Yes i did the tests with and without the coin cr2032 battery
- Yes i tried multiple RAMs modules + video cards both agp or pci

So the motherboard gets no power at all, ( but the power supply turns on anyway ), it's like the motherboard is stuck on suspension mode or something ( that's why the power LED is blinking i suppose ). I have no skills to repair the mobo, sadly i think it's time to toss that away

Sad to hear, but like I mentioned before, the MOSFETs are the main suspect.

Do you think the seller lied about the working status ?

_StIwY_ wrote on 2023-08-25, 15:49:

I have no skills to repair the mobo, sadly i think it's time to toss that away

As a last resort, you can take a hi-res picture of the board and post it here. Then someone of us may spot something unusual.

_StIwY_ wrote on 2023-08-25, 17:26:

Do you think the seller lied about the working status ?

It sounds suspect especially if they didn't post any evidence (e.g. POST screen) of it working beforehand.

On the other hand, sometimes things do spontaneously fail.

I wouldn't junk it though. Even if it's not working, you could always resell it, use it to learn repairs on, or just give it away to someone who could fix it.

Shponglefan wrote on 2023-08-25, 18:15:

It sounds suspect especially if they didn't post any evidence (e.g. POST screen) of it working beforehand. […]
Show full quote

_StIwY_ wrote on 2023-08-25, 17:26:

Do you think the seller lied about the working status ?

It sounds suspect especially if they didn't post any evidence (e.g. POST screen) of it working beforehand.

On the other hand, sometimes things do spontaneously fail.

I wouldn't junk it though. Even if it's not working, you could always resell it, use it to learn repairs on, or just give it away to someone who could fix it.

Exactly. And maybe before the seller removes the board from the case it was working, so who knows.

I've got an Asus A7V133-C from e-waste and boy it was shiny (very rare for any electronics at e-waste). It was working fine for a few times then it suddenly refused to boot. The green power LED indicator is on so the PSU is providing power to the MB but it stays silent after switching working RAM sticks. Capacitors and MOSFETs look okay from the outside; I only have a multimeter so I can't test components further with oscilloscope or other high-end equipment. Sometimes they just stop to work. 🙁