Re: A Mystery, hoping someone can solve for me

Posted on 2024-03-30, 06:54

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Maybe someone needed a 386SX 25 MHz for upgrading another mainboard or as a replacement. This seems to be yours: https://theretroweb.com/motherboards/s/auva-c … mputer-npm16-a0

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Re: A Mystery, hoping someone can solve for me

Posted on 2024-03-30, 06:01

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The 386SX CPU was probably desoldered with hot air or just fell off at some point due to bad soldering. (You can still see the solder remnants on the landings.)

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Re: TYAN "S1662 Pentium Pro" 2nd CPU upgrade

Posted on 2024-03-29, 18:12

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I think this was a good example for a workable division of labor. Luckybob provided the pictures of the components that couldn´t be detected otherwise and I documented everything in text plus pictures stored on this board. All information is available for future upgraders. ... Truth be told, I was …

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Re: TYAN "S1662 Pentium Pro" 2nd CPU upgrade

Posted on 2024-03-29, 09:43

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thx! By the way, the BIOS "05/08/1998" as listed at 'The Retro Web' under the single socket version does work, if you use a Flash-ROM chip that doesn´t provoke the "Unknown Flash Type" message at POST. Filename tyan_s1662_finished.jpg File size 1.87 MiB Views 330 views

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Re: TYAN "S1662 Pentium Pro" 2nd CPU upgrade

Posted on 2024-03-28, 15:13

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Should be able to fire it up with second cpu and do a smoke test at this point. Ohm out power rails make sure their resistance didn’t change much A current limiter would be a good idea, I tested the system a couple of times after adding components, checked for shorts etc. also. Last test was before …

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Re: TYAN "S1662 Pentium Pro" 2nd CPU upgrade

Posted on 2024-03-26, 16:50

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The only component still missing is the Intel APIC chip, that seems to be stuck at customs. Meanwhile I added the 2nd socket, VRM connector and the missing caps and resistors. Filename tyan_s1662_2nd_socket.jpg File size 2 MiB Views 507 views

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Re: Pentium II Overdrive in an Intergraph TD-300

Posted on 2024-03-25, 18:53

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Of course - quit your job, move to the US, order at PE-Connectors, move back home. International trade could make things much more hasslefree. But - and I do support this freedom of choice - no one forces PE-connectors to sell to other parts of the world.

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Re: HELP: Mystery Socket 7 Motherboard Post Fail (Fixed)

Posted on 2024-03-25, 17:38

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Looks like the two caps are in the clock generator circuitry, mabe in the output lines. In this case they should be in the pF range like 10 -22 pF. I can´t see it on the picture, but you can have a look at what they are connected to and check the data sheet of the clock-gen - _if_ it´s related.

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Re: Supermicro P6DNE - Eaten by Varta´s barrel bomb

Posted on 2024-03-25, 15:44

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The traces under ISA slot 3 were restored today and a new socket was soldered into place. A lot of threading wires through damaged vias was necessary here. I also finished the work on the backside and now I´m starting to prepare the landings for the two tristate busdrivers "74ALS245". p6dne_back.JPG …

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Re: Pentium II Overdrive in an Intergraph TD-300

Posted on 2024-03-25, 14:46

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

kingcake wrote on 2024-03-24, 04:08: this site is great! thanks for posting it Except when you live outside the U.S.

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Re: HELP: Mystery Socket 7 Motherboard Post Fail

Posted on 2024-03-24, 08:29

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Have you tried jumpering the "VRE" jumper (J8L1) to default 1-2? (It´s 2-3 in the picture) If you have a multimeter check the voltage at the output pin of the VRM transistor. I have a similar Intel HX mainboard and I remember it´s quite picky about RAM. Did you try different sets of RAM sticks?

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Re: HELP: Mystery Socket 7 Motherboard Post Fail

Posted on 2024-03-24, 07:44

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

https://theretroweb.com/motherboards/s/intel-ag430hx-agate You should start with checking the jumpering.

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Re: Supermicro P6DNE - Eaten by Varta´s barrel bomb

Posted on 2024-03-23, 20:45

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

That´s exactly what mine looked like - even worse in some areas! I spent like one day cleaning it. Supermicro loved the VARTAs so much they even put them on Socket 7 mainboards.

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Re: Supermicro P6DNE - Eaten by Varta´s barrel bomb

Posted on 2024-03-23, 17:57

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

That's Topcat from BCN! :D I wonder if he finished the story over there... Thanks for the link PCH-Patrol - I must have missed this topic completely in 2022. If I remember right, both chips were the same type, so they are both 74F245. For a start I reconstructed all the traces under ISA slot 2 …

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Re: Supermicro P6DNE - Eaten by Varta´s barrel bomb

Posted on 2024-03-23, 07:21

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

While working on the TYAN S1662 and waiting for parts, I thought it might be a good idea to have another go at my Supermicro P6DNE that has been sitting in my shelve for 3 years now gathering dust. I decided to start with replacing the two (probably) buffer chips that came off when I initially …

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Re: FIC 486-GAC-2 and proprietary cache module - Prototype works! Revision in progress.

Posted on 2024-03-23, 07:05

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Great work, this looks brilliant! The "proprietary cache module" just became far less proprietary. I love this kind of stories with happy endings.

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Re: Via MVP3 Cacheable Area

Posted on 2024-03-19, 13:42

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

What you could do is replace the TAG RAM, I have seen far more cases with defective TAG chips than cache SRAM chips. It´s quite easy (SOJ), it´s cheap and no loss when it turns out the TAG chip was not the problem.

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Re: Via MVP3 Cacheable Area

Posted on 2024-03-19, 12:01

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Most of my DFI MVP3 boards have 8nS TAG chips, the ASUS ALI P5A have 8nS - all of them run 100 MHz flawlessly. If yours struggles at 83 or higher it´s either the CPU voltage regulator (-> electrolytics for the capacitor plague era) or one of the SRAM / TAG chips is defective. WIth raising the …

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Re: Via MVP3 Cacheable Area

Posted on 2024-03-19, 06:37

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

On my Lucky Star "5AMVP3" (that I recently upgraded to 1MB L2 cache) CTCM7 also detects a cacheable area of 255 MB. But Write Back L2 and Write Allocation are being enabled by BIOS which is more important for performance than that additional 1MB cacheable RAM. Have you checked for an entry like "T3 …

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Re: FIC 486-GAC-2 and proprietary cache module - Prototype works! Revision in progress.

Posted on 2024-03-18, 17:51

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The only knowledge gained is definite no on 512KB and 1MB cache support with this bios without modding. The alternative BIOS for this FIC chipset platform "4.27GN2A" does support 512K and 1Mb cache, but it comes without video BIOS so an extra ISA graphics card would be necessary. This BIOS version …

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