iraito wrote on 2021-05-18, 19:08:

I can't find a manual for this MB http://www.win3x.org/uh19/motherboard/show/7060
The one here https://www.elhvb.com/mboards/a-trend/manuals/index.html is corrupted, i need some help with setting the jumpers for my pentium 200 mmx

Excuse a piece of information, what CPU do you currently have on the Motherboard?
Seeing the images (photo of the link), the Pentium MMX CPU doesn't seem supported, I see only one mosfet, and if you don't have two, you can't put a Dual Voltage CPU, the only solution is the Pentium Overdrive MMX, but beyond to be rare I think it will also be expensive.
However if you like you can write here how are the jumpers (eg. JP1 2-3 Closed or other), maybe you can understand if there are the jumpers for the dual voltage and those of the VCore for the MMX (2.8V), however, I do not believe that there is this approach.

PC@LIVE wrote on 2021-05-18, 19:48:

Excuse a piece of information, what CPU do you currently have on the Motherboard? Seeing the images (photo of the link), the Pen […]
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iraito wrote on 2021-05-18, 19:08:

I can't find a manual for this MB http://www.win3x.org/uh19/motherboard/show/7060
The one here https://www.elhvb.com/mboards/a-trend/manuals/index.html is corrupted, i need some help with setting the jumpers for my pentium 200 mmx

Excuse a piece of information, what CPU do you currently have on the Motherboard?
Seeing the images (photo of the link), the Pentium MMX CPU doesn't seem supported, I see only one mosfet, and if you don't have two, you can't put a Dual Voltage CPU, the only solution is the Pentium Overdrive MMX, but beyond to be rare I think it will also be expensive.
However if you like you can write here how are the jumpers (eg. JP1 2-3 Closed or other), maybe you can understand if there are the jumpers for the dual voltage and those of the VCore for the MMX (2.8V), however, I do not believe that there is this approach.

It got worse, after installing the MMX i went back to the 133mhz and now the bios freezes ? did i kill the mobo or just the mosfet?
I can enter the bios setup but at system configuration screen i get a frozen screen
https://streamable.com/66ea9g

Did you set the jumpers back to 133MHz?

Oh and this board, even though "P55C" is mentioned in the manual, does NOT support MMX CPUs or any other split-voltage CPUs. I will adjust the page accordingly.

evasive wrote on 2021-05-19, 11:37:

Did you set the jumpers back to 133MHz?

Oh and this board, even though "P55C" is mentioned in the manual, does NOT support MMX CPUs or any other split-voltage CPUs. I will adjust the page accordingly.

I did, now the bios always freeze at that screen, i already found a decently cheap motherboard for my MMX shenanigans but i would like to recover this, any suggestion ?

load bios defaults/ save and exit
load setup defaults / save and exit

Can you try setting the CPU for 120MHz to see if it runs at a slightly slower speed?

evasive wrote on 2021-05-19, 11:50:

load bios defaults/ save and exit
load setup defaults / save and exit

Can you try setting the CPU for 120MHz to see if it runs at a slightly slower speed?

It doesn't work, i tried multiple lower clocks and resetting the CMOS, it's always frozen on that damn screen.

iraito wrote on 2021-05-19, 08:30:

It got worse, after installing the MMX i went back to the 133mhz and now the bios freezes ? did i kill the mobo or just the mos […]
Show full quote

PC@LIVE wrote on 2021-05-18, 19:48:

Excuse a piece of information, what CPU do you currently have on the Motherboard? Seeing the images (photo of the link), the Pen […]
Show full quote

iraito wrote on 2021-05-18, 19:08:

I can't find a manual for this MB http://www.win3x.org/uh19/motherboard/show/7060
The one here https://www.elhvb.com/mboards/a-trend/manuals/index.html is corrupted, i need some help with setting the jumpers for my pentium 200 mmx

Excuse a piece of information, what CPU do you currently have on the Motherboard?
Seeing the images (photo of the link), the Pentium MMX CPU doesn't seem supported, I see only one mosfet, and if you don't have two, you can't put a Dual Voltage CPU, the only solution is the Pentium Overdrive MMX, but beyond to be rare I think it will also be expensive.
However if you like you can write here how are the jumpers (eg. JP1 2-3 Closed or other), maybe you can understand if there are the jumpers for the dual voltage and those of the VCore for the MMX (2.8V), however, I do not believe that there is this approach.

It got worse, after installing the MMX i went back to the 133mhz and now the bios freezes ? did i kill the mobo or just the mosfet?
I can enter the bios setup but at system configuration screen i get a frozen screen
https://streamable.com/66ea9g

From what you write you have forced the MMX CPU, to go with single voltage, so 3.3V or more.
This could have hurt, or it could have created some problem that is difficult to solve, the fact that the screen freezes in the BIOS could be a consequence, but saying what is wrong is not possible, you should test the components you use in another PC similar, if you find the same problem something is wrong, and you have to try to see what it is.
If instead they are fine in another PC, it is something in the motherboard, the only test you can do is change the jumper setting and try lower frequencies, for example multi 1.5X and FSB 50MHz, corresponding to a P75, if it works try raising it up to the frequency where the problem recurs.

PC@LIVE wrote on 2021-05-19, 19:27:

From what you write you have forced the MMX CPU, to go with single voltage, so 3.3V or more. This could have hurt, or it could h […]
Show full quote

iraito wrote on 2021-05-19, 08:30:

It got worse, after installing the MMX i went back to the 133mhz and now the bios freezes ? did i kill the mobo or just the mos […]
Show full quote

PC@LIVE wrote on 2021-05-18, 19:48:

Excuse a piece of information, what CPU do you currently have on the Motherboard?
Seeing the images (photo of the link), the Pentium MMX CPU doesn't seem supported, I see only one mosfet, and if you don't have two, you can't put a Dual Voltage CPU, the only solution is the Pentium Overdrive MMX, but beyond to be rare I think it will also be expensive.
However if you like you can write here how are the jumpers (eg. JP1 2-3 Closed or other), maybe you can understand if there are the jumpers for the dual voltage and those of the VCore for the MMX (2.8V), however, I do not believe that there is this approach.

It got worse, after installing the MMX i went back to the 133mhz and now the bios freezes ? did i kill the mobo or just the mosfet?
I can enter the bios setup but at system configuration screen i get a frozen screen
https://streamable.com/66ea9g

From what you write you have forced the MMX CPU, to go with single voltage, so 3.3V or more.
This could have hurt, or it could have created some problem that is difficult to solve, the fact that the screen freezes in the BIOS could be a consequence, but saying what is wrong is not possible, you should test the components you use in another PC similar, if you find the same problem something is wrong, and you have to try to see what it is.
If instead they are fine in another PC, it is something in the motherboard, the only test you can do is change the jumper setting and try lower frequencies, for example multi 1.5X and FSB 50MHz, corresponding to a P75, if it works try raising it up to the frequency where the problem recurs.

I took out everything and lowered the frequency, the only think that behaves weirdly is the EDO ram, if i took out a memory out of the two i get a black screen, if i move them around in different slots i get a black screen, i want to specify that the first time i used the MMX the mobo saw it as a pentium-s 167, it worked and i was able to test quake with it, i got 30fps too, after i rebooted i got the frozen screen.

Typically, this era of P54 boards would not support more than a 166 because the regulator topped out near 15W and officially, P200 and P200MMX were a little over that. I am not seeing the value of trying to troubleshoot the board with a P55 still as it's probably pushing over 15W when used at 3.3V core at 166. If you wanna see if it still works as designed put a P54 in it. The overdrives seem to be specifically designed to limit current draw and max at 15W for this reason.

BitWrangler wrote on 2021-05-19, 20:48:

Typically, this era of P54 boards would not support more than a 166 because the regulator topped out near 15W and officially, P200 and P200MMX were a little over that. I am not seeing the value of trying to troubleshoot the board with a P55 still as it's probably pushing over 15W when used at 3.3V core at 166. If you wanna see if it still works as designed put a P54 in it. The overdrives seem to be specifically designed to limit current draw and max at 15W for this reason.

I did, i'm testing this with a pentium 133 that worked well for months.

Well guys since i don't have much hope on this mobo unless i flash it, is the attached one MMX compatible ? just asking to be sure

iraito wrote on 2021-05-19, 21:32:

Well guys since i don't have much hope on this mobo unless i flash it, is the attached one MMX compatible ? just asking to be sure

That big heatsink with what looks like a linear VRM certainly gives that impression - but the CPU fan wires obscure the part of the board where the relevant jumpers would be, and the VRM socket next to the CPU makes you wonder as well...

Also, this isn't an ATC-1545.

I'd go for a yes and no on that one. There's a socket hiding behind the fan connector that looks like a regulator upgrade socket. You'd have to put a regulator in it to enable split voltage operation.

edit: Also manufacturers would release these with a "Swear on me mom" it'll support MMX, but the BIOS support never transpired, or you'd have to buy their regulator and replacement BIOS chip at about $10 less than a new motherboard.

This board is designed for up to pentium 200 due to single voltage regulator due to low end board and VX. Not intended for MMX.

Also the firmware ID it as -S which is confirms can't use MMX correctly.

What make it this work well if you have a motherboard with switching regulator and more than 3 VRMs circuits and newer. TX chipset is more likely can.
Means have to hunt for another one.

Cheers,

This one is compatible with MMX up to 233 apparently, but untested and barebone BUT really cheap, i might go for this one.

At the end i went with this one, it supports MMX (thankfully it has written REV 3.37 so i know for sure) and it has 2 DIMM slots, now i just hope i didn't destroy the 200MMX i inserted in the 1545.

GA-586VX Motherboard […]
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GA-586VX Motherboard

- Award BIOS ID string 07/11/97-i430VX-8669-2A59GG0CC-00
- 4-72 pin SIMM slots (8-128meg 4/8/16/32MB 60~70ns EDO/FPM DRAM)
- 2-168pin DIMM slot (8-64meg 8/16/32/64 PC66/PC100 64/72bit SDRAM)
64MB DIMMs need to have 32 chips in total, 16 on each side,
any fewer means high-density chips which the 430VX chipset cannot handle.
It's a hardware limitation that a bios upgrade will not cure.
- 4-32bit PCI Bus slots
- 3-16bit ISA slots
- 160pin 512K upgrade pipeline burst SRAM COAST 3.0+ module
- 256k or 512K Pipeline Burst Sync. L2 Cache onboard
- AWARD 95 Auto-Detect Flash Bios with Energy Mgmt.
- Supports LBA Mode Control & Large Disk DOS Compatibility.
- Green PC Connector
- PS/2 Mouse Connector
- USB connectors
- Intel Triton i430VX PCIset SB82437VX chipset
- BENCHMARQ3287/DALLAS DS12887A/ODIN 12C887 RTC with builtin cmos battery
- P55c Voltage Regulator
- Supports 2.8v/3.3v/3.5v CPU's and multipliers 1.5x/2x/2.5x/3x
- 321pin ZIF socket 7 which supports these processors:
INTEL Pentium P54C(75-200MHz), P54CT(125/150/166),
P54CTB(150/166/180/200), P55C(150/166/200/233mmx)
AMD K5 (P-75/90/100/120/133/166/200)
Cyrix 6x86-100/110/120/133(P-120+/P-133+/P-150+/P-166+),
Cyrix 6x86L (P-150+/P-166+(2.8V))
- Supports 60/66 MHz external clock speeds
- Multi-I/O chip supports:
2 PCI Enhanced IDE Ports (Supports 4 Devices PIO 0-4)
2 High Speed Serial Ports (16550 UART Compatible)
1 Enhanced Parallel Port (SPP, EPP, ECP capable)
1 Floppy Drive Port (Supports 2 Floppy Drives)
- Manufactured by: Giga-Byte

iraito wrote on 2021-05-20, 07:14:

At the end i went with this one, it supports MMX (thankfully it has written REV 3.37 so i know for sure) and it has 2 DIMM slots, now i just hope i didn't destroy the 200MMX i inserted in the 1545.

Don't expect too much from the DIMM slots. i430VX was the first chipset to support SDRAM and support is very limited. It can handle max 16Mb per chip, so max 32MB per DIMM on DIMMs with 16 chips. Any more recent higher density stuff (64Mb chips etc) will only be used at 1/4 of capacity or less.

So max SDRAM capacity is 64MB with two DIMM slots, where you can go up to 128MB with (EDO) SIMMs. Note that the chipset can only cache 64MB, and that period correct software won't even need half that anyway.

dionb wrote on 2021-05-20, 10:09:

iraito wrote on 2021-05-20, 07:14:

At the end i went with this one, it supports MMX (thankfully it has written REV 3.37 so i know for sure) and it has 2 DIMM slots, now i just hope i didn't destroy the 200MMX i inserted in the 1545.

Don't expect too much from the DIMM slots. i430VX was the first chipset to support SDRAM and support is very limited. It can handle max 16Mb per chip, so max 32MB per DIMM on DIMMs with 16 chips. Any more recent higher density stuff (64Mb chips etc) will only be used at 1/4 of capacity or less.

So max SDRAM capacity is 64MB with two DIMM slots, where you can go up to 128MB with (EDO) SIMMs. Note that the chipset can only cache 64MB, and that period correct software won't even need half that anyway.

That's totally fine for me, i still have a 32mb pc100 memory bank double layered that i used on a similar pc in the 90's, it's mostly the speed i care about, 32mb is the max i'm gonna ever use on a pentium 1.

looking forword for pictures for this page then:
http://www.win3x.org/uh19/motherboard/show/2753