What motherboard is it? Any pics of any of the error messages?

https://theretroweb.com/motherboards/s/pcpart … 500n-35-8212-32

The chipset is Intel 82371FB (PIIX) according to post string.
No error message pic just a flashing "-" key.
Just analyzer card post codes 63,62.

Hmm, did you change the jumper settings for the cache to reflect the fact you have removed it?

Unfortunately removed all cache jumpers and still the same.
I even unplugged the keyboard waited for the error message plugged it in and hit f1. It then did the same thing. Cant reset pc either.

vacatedboat wrote on 2023-03-05, 08:38:

I have a pentium-s 166 machine that fails to boot from a fdd boot disk. So i have video card, keyboard, power and the fdd connec […]
Show full quote

I have a pentium-s 166 machine that fails to boot from a fdd boot disk.
So i have video card, keyboard, power and the fdd connected only. Removed all cache too. So it boots until the second splash screen. It does seek the floppy dive and makes the standard grr noise.
Things ive noticed.
Numlock lights up at halt and then the keyboard doesn't respond so no ctrl alt del to reset. I have a post card analyzer and it halts at 63,62 everytime. The award bios talks about numlock and typeomatic stuff as those codes and other things i dont understand.
I have tried loading default bios settings but the same. I feel the answer is staring me in the face its obvious. But i cant see it.
Only thing i haven't tried is flashing the bios. Think i have the latest though and the RTC hasnt been replaced either.
Many thanks for help

One of the most important and basic things of every computer is the RAM.
You did not mention it with a single word.
So you have 2 times 4MB in bank1?
Is the RAM known good (tested in another system)?
EDIT: 2 times 16MB EDO?

This is the only board i have that supports edo ram unfortunately. Yes 2 x 16meg. I guess never thought to try other ram sticks as my limited experience bad ram never gets past the boot/post screen and my spkr beeps. I will see if i have some fpm ram stick and try that.
I also wondered as my video card is ISA and its not to my knowledge pnp so i ordered a pci card in case of a irq conflict or such.
See how it goes. Thanks for your input

Way back I had some dumbass board that "couldn't believe" that it didn't have a HDD, and it would just hang up waiting for it to say it was there, even if USB or floppy boot selected.

However, I notice we're not seeing the ECSD message, so that could be scrambled... clear CMOS with the clear jumper, reset everything in setup, then boot and wait for it to update ECSD, can take 2 mins or so, hopefully it then says success, saves it and boots.

CoffeeOne wrote on 2023-03-06, 23:35:

One of the most important and basic things of every computer is the RAM. You did not mention it with a single word. So you have […]
Show full quote

vacatedboat wrote on 2023-03-05, 08:38:

I have a pentium-s 166 machine that fails to boot from a fdd boot disk. So i have video card, keyboard, power and the fdd connec […]
Show full quote

I have a pentium-s 166 machine that fails to boot from a fdd boot disk.
So i have video card, keyboard, power and the fdd connected only. Removed all cache too. So it boots until the second splash screen. It does seek the floppy dive and makes the standard grr noise.
Things ive noticed.
Numlock lights up at halt and then the keyboard doesn't respond so no ctrl alt del to reset. I have a post card analyzer and it halts at 63,62 everytime. The award bios talks about numlock and typeomatic stuff as those codes and other things i dont understand.
I have tried loading default bios settings but the same. I feel the answer is staring me in the face its obvious. But i cant see it.
Only thing i haven't tried is flashing the bios. Think i have the latest though and the RTC hasnt been replaced either.
Many thanks for help

One of the most important and basic things of every computer is the RAM.
You did not mention it with a single word.
So you have 2 times 4MB in bank1?
Is the RAM known good (tested in another system)?
EDIT: 2 times 16MB EDO?

I re tested the edo ram in bank 0 and it fails to boot computer but works fine in bank 1.
I managed to installed 2 x 8meg fpm sticks in bank 0 and the computer posted but no change. It still hangs with frozen keyboard.

Could there be a problem with your floppy drive?

Do you have any other bootable things you can try? A hdd with a OS on it perhaps? Or a gotek? Or a xt-ide with bootable cf on it?

BitWrangler wrote on 2023-03-07, 03:30:

Way back I had some dumbass board that "couldn't believe" that it didn't have a HDD, and it would just hang up waiting for it to say it was there, even if USB or floppy boot selected.

However, I notice we're not seeing the ECSD message, so that could be scrambled... clear CMOS with the clear jumper, reset everything in setup, then boot and wait for it to update ECSD, can take 2 mins or so, hopefully it then says success, saves it and boots.

Ok so re tried my cf to ide card and also got the old quantum fireball ide out but made no difference.
So i applied the jumper to clear cmos and booted. Reset/loaded bios defaults then saved. I removed the jumper and booted. The only difference was it halts with cmos checksum error but press f1 and it locks up the keyboard again. Same result

I might next try backing up the bios and re flash with one of the other versions.

You may try to set the cpu at 100MHz, that relieves all stress on it so you'll probably the that one out.
If that works you may have encountered one of the many remarked ones. Mostly they will run fine but some will struggle.
Or did you set the main board with split voltage? That's ment for the MMX P55 and also will make things fast from stable. The P54c needs a linear voltage.

Also try to attach a HDD because some systems actually require to have one attached.

Could the lack of cache be an issue? Does the board expect it to be present?

waterbeesje wrote on 2023-03-07, 08:25:

You may try to set the cpu at 100MHz, that relieves all stress on it so you'll probably the that one out. If that works you may […]
Show full quote

You may try to set the cpu at 100MHz, that relieves all stress on it so you'll probably the that one out.
If that works you may have encountered one of the many remarked ones. Mostly they will run fine but some will struggle.
Or did you set the main board with split voltage? That's ment for the MMX P55 and also will make things fast from stable. The P54c needs a linear voltage.

Also try to attach a HDD because some systems actually require to have one attached.

Could the lack of cache be an issue? Does the board expect it to be present?

Had a few mins and reduced to 100mhz but same. It did display 100mhz. Afaik this MB doesn't support mmx cpu. I changed the jumper to 3.53 to 3.5Volts but still the same. It was at 3.38V.
I had previously spent many hours getting a coast stick and 28dip sram to work but nothing made it happen. If it wont work without cache thats going to be disappointing.
Never knew pentiums could be so picky

I once encountered specific keyboard that would keep the system from working correctly. (Usb) others worked.

Doubt that is the case here but figured I’d mention it

Take the system down to absolutely bare minimum and switch out all the components one by one.

If nothing, try bios settings one by one.

vacatedboat wrote on 2023-03-07, 07:18:

CoffeeOne wrote on 2023-03-06, 23:35:

One of the most important and basic things of every computer is the RAM. You did not mention it with a single word. So you have […]
Show full quote

vacatedboat wrote on 2023-03-05, 08:38:

I have a pentium-s 166 machine that fails to boot from a fdd boot disk. So i have video card, keyboard, power and the fdd connec […]
Show full quote

I have a pentium-s 166 machine that fails to boot from a fdd boot disk.
So i have video card, keyboard, power and the fdd connected only. Removed all cache too. So it boots until the second splash screen. It does seek the floppy dive and makes the standard grr noise.
Things ive noticed.
Numlock lights up at halt and then the keyboard doesn't respond so no ctrl alt del to reset. I have a post card analyzer and it halts at 63,62 everytime. The award bios talks about numlock and typeomatic stuff as those codes and other things i dont understand.
I have tried loading default bios settings but the same. I feel the answer is staring me in the face its obvious. But i cant see it.
Only thing i haven't tried is flashing the bios. Think i have the latest though and the RTC hasnt been replaced either.
Many thanks for help

One of the most important and basic things of every computer is the RAM.
You did not mention it with a single word.
So you have 2 times 4MB in bank1?
Is the RAM known good (tested in another system)?
EDIT: 2 times 16MB EDO?

I re tested the edo ram in bank 0 and it fails to boot computer but works fine in bank 1.
I managed to installed 2 x 8meg fpm sticks in bank 0 and the computer posted but no change. It still hangs with frozen keyboard.

Hmm,
If I looked into the correct manual, 2 times 16MB EDO should work either in both bank 0 and bank 1.
So I would say your 2 times 16MB are not working in the board.
But (weird!) 2 times 8MB should only work in bank 1.
So something is wrong.

Are you sure the board is a "PCPartner MB500N"?

But still I am 99% sure that you have a RAM problem. Get other RAM and try again. Also try to use 2 identical modules.

Hmm,
If I looked into the correct manual, 2 times 16MB EDO should work either in both bank 0 and bank 1.
So I would say your 2 times 16MB are not working in the board.
But (weird!) 2 times 8MB should only work in bank 1.
So something is wrong.

Are you sure the board is a "PCPartner MB500N"?

But still I am 99% sure that you have a RAM problem. Get other RAM and try again. Also try to use 2 identical modules.
[/quote]

Will buy some more ram sticks. Fingers crossed.
There are so far subtle differences with the pcpartner mb500n like I have jp38 and its not in the manual. Was thinking of using my meter and buzzing it out. Also j6 only has one row of pins. Mine has 2.

vacatedboat wrote on 2023-03-08, 03:18:

There are so far subtle differences with the pcpartner mb500n like I have jp38 and its not in the manual. Was thinking of using my meter and buzzing it out. Also j6 only has one row of pins. Mine has 2.

With these subtle differences and the hang at POST 63 where all the detected motherboard hardware is enabled, I believe you may have the wrong BIOS for your board.

Do you see a "35-82xx-xx" marking on your board? If so, what are the numbers on the xx's?
And what's written on the chipset and on the Multi I/O chip?

Can you make a hi-res picture of your board so we can see the details?

Jan

Chkcpu wrote on 2023-03-08, 14:58:

With these subtle differences and the hang at POST 63 where all the detected motherboard hardware is enabled, I believe you may […]
Show full quote

vacatedboat wrote on 2023-03-08, 03:18:

There are so far subtle differences with the pcpartner mb500n like I have jp38 and its not in the manual. Was thinking of using my meter and buzzing it out. Also j6 only has one row of pins. Mine has 2.

With these subtle differences and the hang at POST 63 where all the detected motherboard hardware is enabled, I believe you may have the wrong BIOS for your board.

Do you see a "35-82xx-xx" marking on your board? If so, what are the numbers on the xx's?
And what's written on the chipset and on the Multi I/O chip?

Can you make a hi-res picture of your board so we can see the details?

Jan

On the motherboard its 35-8212-32. Here are pics i have. They were taken at different time oeriods so ignore the coast stick etc hope they are clear and have the numbers.

The 35-8212-32 marking cleary identifies your board as a Vtech / PCPartner MB500N.
Also both pictures on https://theretroweb.com/motherboards/s/pcpart … 500n-35-8212-32 look identical to yours, including the double J6 jumpers and the J38 jumper near the keyboard controller.
So the documentation is lacking here, probably from an earlier board revision.

Do you have an (E)EPROM programmer? If so, please dump the BIOS to file so I can take a look and check what POST 63 is doing. Unfortunately, the 12/19/95-i82371-2A59CV3KC-00 BIOS on theretroweb is corrupted and can’t be used to crosscheck.

PCPartner uses I/O chips from different manufacturers on their boards. So a particular board can have 2 or 3 different BIOSes, one for each I/O vendor. These BIOSes often have the same date and version number.
Yours has an UMC I/O chip, so only a BIOS for UMC I/O can be used.

Did you try with the Tag RAM chip (near the battery) removed?
Another thing to try is disabling the COM and LTP ports in the BIOS Setup. This may help if your present BIOS isn't meant for the UMC I/O.

Cheers, Jan

Chkcpu wrote on 2023-03-09, 15:06:

The 35-8212-32 marking cleary identifies your board as a Vtech / PCPartner MB500N. Also both pictures on https://theretroweb.com […]
Show full quote

The 35-8212-32 marking cleary identifies your board as a Vtech / PCPartner MB500N.
Also both pictures on https://theretroweb.com/motherboards/s/pcpart … 500n-35-8212-32 look identical to yours, including the double J6 jumpers and the J38 jumper near the keyboard controller.
So the documentation is lacking here, probably from an earlier board revision.

Do you have an (E)EPROM programmer? If so, please dump the BIOS to file so I can take a look and check what POST 63 is doing. Unfortunately, the 12/19/95-i82371-2A59CV3KC-00 BIOS on theretroweb is corrupted and can’t be used to crosscheck.

PCPartner uses I/O chips from different manufacturers on their boards. So a particular board can have 2 or 3 different BIOSes, one for each I/O vendor. These BIOSes often have the same date and version number.
Yours has an UMC I/O chip, so only a BIOS for UMC I/O can be used.

Did you try with the Tag RAM chip (near the battery) removed?
Another thing to try is disabling the COM and LTP ports in the BIOS Setup. This may help if your present BIOS isn't meant for the UMC I/O.

Cheers, Jan

Ok i no longer have the tag ram in and also did try misus the com/lpt ports.
I have the .bin file but where can i put it? Its not allowed. I tried it in zip folder but also not possible.
I did however try to rom dump it to the retroweb discord server. Its the one with my user name vacatedboat
Hope it works. Thanks