10 - 22µF 25V should be fine at all the positions.
The x-tal at the oscillator chip is missing also.

Wow, that's a good looking VLB board! Nice, hope you get it fixed!

majestyk wrote on 2022-06-06, 08:43:

10 - 22µF 25V should be fine at all the positions.
The x-tal at the oscillator chip is missing also.

Wooow, You saw that, and i didn't! Thanks, i will solder capacitors first, and i will try to find same oscillator as on picture. 16.??? I cannot see the whole number.

Doornkaat wrote on 2022-06-06, 08:45:

Wow, that's a good looking VLB board! Nice, hope you get it fixed!

Thanks, i also hope i could fix it.

majestyk wrote on 2022-06-06, 08:43:

10 - 22µF 25V should be fine at all the positions.
The x-tal at the oscillator chip is missing also.

Is it good to solder some "close value" oscillator there, or it has to be exactly the same? I cannot see the number, as far i can see it is 16.3C55?? To blurry...

The oscillator quartz will probably be 14.7456 MHz.

majestyk wrote on 2022-06-06, 10:58:

The oscillator quartz will probably be 14.7456 MHz.

Thanks a lot, i will try to buy it and solder all of this components, and i will let You know if it's working.
Thanks again!

Wouldn't the usual crystal be 14.318? The SC462 datasheet is here: https://www.datasheetarchive.com/pdf/download … am%2520circuits

It's only 3% difference, so I don't think it'll cause any problems either way.

14.318mhz reference clock is a must for all chipsets, even to this day, anything lower or higher will desync all timers in the system. You should first populate that xtal and test mb before proceeding with restoration.

snufkin wrote on 2022-06-06, 16:54:

Wouldn't the usual crystal be 14.318? The SC462 datasheet is here: https://www.datasheetarchive.com/pdf/download … am%2520circuits

It's only 3% difference, so I don't think it'll cause any problems either way.

I already order 14.7456 from ebay. So You think it will work even with this one?

SSTV2 wrote on 2022-06-06, 21:19:

14.318mhz reference clock is a must for all chipsets, even to this day, anything lower or higher will desync all timers in the system. You should first populate that xtal and test mb before proceeding with restoration.

You think i will not have a working MBO with 14.7456?

It would start, but don't expect proper operation from it. By the way, these 14.318M xtals are very common, you can find them almost on all video cards/motherboards. Local electronics stores would also have them at hand.

SSTV2 wrote on 2022-06-07, 21:49:

It would start, but don't expect proper operation from it. By the way, these 14.318M xtals are very common, you can find them almost on all video cards/motherboards. Local electronics stores would also have them at hand.

Thanks man, i will search for one of them. Will let You know if it's working, after soldering all the missing stuff 😀

butjer1010 wrote on 2022-06-08, 11:47:

SSTV2 wrote on 2022-06-07, 21:49:

It would start, but don't expect proper operation from it. By the way, these 14.318M xtals are very common, you can find them almost on all video cards/motherboards. Local electronics stores would also have them at hand.

Thanks man, i will search for one of them. Will let You know if it's working, after soldering all the missing stuff 😀

For now everything works, now it is time for testing other components 😀
Thanks a thousand times!!

snufkin wrote on 2022-06-06, 16:54:

Wouldn't the usual crystal be 14.318? The SC462 datasheet is here: https://www.datasheetarchive.com/pdf/download … am%2520circuits

It's only 3% difference, so I don't think it'll cause any problems either way.

It works, thanks a lot!

majestyk wrote on 2022-06-06, 10:58:

The oscillator quartz will probably be 14.7456 MHz.

I solder 14.318 as everybody else were suggesting, and it works. Thanks a lot man, capacitors are perfect.

SSTV2 wrote on 2022-06-07, 21:49:

It would start, but don't expect proper operation from it. By the way, these 14.318M xtals are very common, you can find them almost on all video cards/motherboards. Local electronics stores would also have them at hand.

I cannot install windows or dos on that machine! I tried 3 different isa ide controllers, 4 different hard disks, 2 different memories, but it always stops on some point. What could be the problem i don't know, but maybe i will try to solder 14.7456 xtal, just to see if will work better?
I have one disk with dos 6.22 on it, but it wont load every time. Sometimes stops at "himem is testing extended memory", sometimes loads dos perfectly??? Weird....

The correct frequency of the oscillator is 14.318 MHz as snufkin pointed out. The datasheet is always right 😀

I think your current problem has some other cause. Did you try installing DOS or WIN with all 9 cache chips removed? Is the cache jumpering 100% correct?
Same goes for the CPU voltage jumpering.

majestyk wrote on 2022-06-11, 16:23:

The correct frequency of the oscillator is 14.318 MHz as snufkin pointed out. The datasheet is always right 😀

I think your current problem has some other cause. Did you try installing DOS or WIN with all 9 cache chips removed? Is the cache jumpering 100% correct?
Same goes for the CPU voltage jumpering.

CPU voltage is ok, 3.3V (intel DX4 100, but it works at 120MHz - with cooler), but i didn't tried installing without cache chips. Thanks, i will try without them and see the outcome.