Re: This motherboard—can someone identify it?

Posted on 2023-08-06, 16:11

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The capital letter on the AWARD BIOS chips with white paper labels can tell the mainboard manufacturer. "D" is for Abit "F" is for FIC "E" is for Chaintech "I" is for Aquarius Systems "J" is for Jetway .... Please note that the letter only occasionally corresponds with the first letter of the brand …

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Re: Super Socket 7 Board not going POST

Posted on 2023-08-01, 05:27

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The Epox MVP3-Gx mainboards were hit by the capacitor plague big time. Most instabilities they show are directly or indirectly caused by dried out electrolytics. Sometimes you couldn´t even finish a windows installation. Dead electrolytics also make the chipset and CPU overheat. It´s highly …

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Re: Juko ST OEM motherboard @12MHz and 8087-1 @12MHz - Has anyone else had success?

Posted on 2023-08-01, 04:47

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Most at/XT power supplies allow you to trim the 5v rail up and down . If your board doesn’t further regulate the 5 volt rail you could try overclocking the old fashioned way. I have several AT PSUs - none of them allows the user to adjust the 5V rail. Can you give an example for an AT-PSU with …

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Re: Can't install Windows xp

Posted on 2023-07-29, 04:56

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

ElectroSoldier wrote on 2023-07-28, 23:54: A page fault in a none paged area basically means it looked into a memory address and that address was empty when it shouldnt have been. Test you RAM with Memtest86. That´s the common explanation, but don´t hold your breath, I have seen countless cases …

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Re: Can't install Windows xp

Posted on 2023-07-28, 19:01

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I assume you are using a slipstreamed XP-SP2 CD?

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Re: Where the heck do I get capacitors?

Posted on 2023-07-28, 17:48

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The advantage here is the caps are for a microphone. No high voltages and no surges to be expected, no high ripple currents, no high frequencies, no extreme temperatures. Although I´m usually very picky when it comes to sourcing capacitors I would be very relaxed here - nearly _every_ capacitor will …

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Re: 286 "CHIPS" mainboard with missing parts...

Posted on 2023-07-27, 17:59

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

DACK2 might be just "slightly" damaged, it´s between IRQ3 and TC (both TTL) so a short caused by a tilted ISA card is not a big deal. In my case it was DRQ2 that´s between -5V and -12V. A tilted card will wreak havoc on the output stage.

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Re: 3x Azza PT-5IT V2.x semi dead ?

Posted on 2023-07-27, 15:44

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

1. dead and no signal 32KHz, board dead anyway. 2. alive but lower than expected signal, also on another working board; bad 32K 3. 32KHz going from 0 to 5MHz (I don't know how), all other crystals I checked behaved the same on this board, probably bad southbridge. I can confirm that, I had several …

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Re: 286 "CHIPS" mainboard with missing parts...

Posted on 2023-07-27, 15:30

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You are golden - 82C206 can be found everywhere, in my case I´m looking for a super rare SL82C362SX.... https://www.vogons.org/viewtopic.php?f=46&t=87740&hilit=transplant&start=20 Btw - are you happy with your DS4024? I recently nearly ordered one, but wanted to make sure first it can handle 133, …

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Re: Epox 8KTA3+ BIOS

Posted on 2023-07-26, 19:19

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Well done, so at least this problem can be ruled out. Strange things can happen when the VRMs are not 100% stable.

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Re: Epox 8KTA3+ BIOS

Posted on 2023-07-26, 19:10

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Did this mainboard that was released at the peak of the capacitor plague ever undergo a recap in it´s VRM section? This is what comes to my mind when there are any stability issues at higher frequencies - it doesn´t explain why setmul fails to set lower multipliers though.

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Re: mysterious (386) CGS chipset, info needed

Posted on 2023-07-26, 15:44

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The "MT / QC / O.K." sticker means "Modula Tech".

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Re: 286 "CHIPS" mainboard with missing parts...

Posted on 2023-07-25, 17:23

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I had a similar case recently with a 386 mainboard. Video, keyboard etc. all working fine, but I couldn´t boot from floppy or hd. The reason was a missing DRQ2 signal from the chipset - probably blown by a short when someone had taken out an ISA card while the system was still running.

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Re: Need help getting Promise EIDE 2300 Plus (VLB) working?

Posted on 2023-07-24, 20:14

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The GIO-VT normally has a promise VLB IDE controller onboard. To disable it, several jumpers need to be altered. (There´s also a version without this chip, then the Winbond super-I/O takes care of IDE and must be disabled.) FIC_486GIOVTa.jpg Did you check all the settings in the manual? FIC_486-gio- …

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Re: Jumpering "RAINBOW" 286 mainboard to address both DIP and SIPP RAM

Posted on 2023-07-24, 17:37

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Each pair of banks can be configured seperately. Register "6AH" for banks 0/1 (DIP): Filename neat_bank0_1.JPG File size 183.24 KiB Views 308 views and 6CH for banks 2/3 (SIPP): Filename neat_bank2_3.JPG File size 184.91 KiB Views 308 views The second value right of the entry for chip-size is for …

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Re: Jumpering (unknown) 286 Mainboard to address both DIP and SIPP RAM

Posted on 2023-07-24, 08:43

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I tested the 4 RAS lines today, they are wired as follows: RAS bank0 (jumper pin1) -> 33R -> buffer O3/I3 -> 82C212 pin80 RAS bank1 (jumper pin1) -> 33R -> buffer O7/I7 -> 82C212 pin79 RAS bank2 (jumper pin1) -> 33R -> buffer O2/I2 -> 82C212 pin78 RAS bank3 (jumper pin1) -> 33R -> buffer O0/I0 -> …

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Re: Jumpering (unknown) 286 Mainboard to address both DIP and SIPP RAM

Posted on 2023-07-23, 13:54

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Just checked the RAS and CAS lines between memory chips / sockets and jumpers: ______________________ x-CAS02-x | x-RAS2-x | x-RAS3-x x-CAS21-x | x-RAS0-x | x-RAS1-x x-CAS22-x | x-CAS31-x | x-CAS32-x x-CAS01-x | x-CAS12-x | x-CAS11-x _______________________ (first digit=bank, second digit=DIP column …

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Jumpering "RAINBOW" 286 mainboard to address both DIP and SIPP RAM

Posted on 2023-07-23, 07:10

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I got this Chips & Technologies based 286 mainboard with 1MB onboard DIP RAM and have been trying to add another 4MB (4 x 1MB 9-chip SIPP sticks) for a total of 5MB - so far with no success. Similar boards with this chipset have just one or two jumpers to turn the SIPP sockets on or off and …

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Re: Replacing Tantalum (12v/5v rail filters) capacitors with through hole ceramics (not MLCC)?

Posted on 2023-07-23, 05:05

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The risk of Tantalums shorting / exploding increases dramatically when they are operated near their nominal voltages. This is why on mainboards in almost all cases the tantalums in the +12V and -12V rails fail, when they have a nominal voltage of 16V. This can be avoided by choosing the next higher …

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Re: Abit AB-FA3 FPU woes

Posted on 2023-07-21, 17:38

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Have you tried with cache and TAG chips removed? What´s your exact CPU and FPU type/ frequency of the oscillator?

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