VOGONS


First post, by DoomGuy II

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I just bought a 486 PCI based motherboard off of EBay, which is an Mtech R418W2 according to what I've read.

$_57.JPG

Unfortunately, I can't seem to find the manual and jumper instructions for this specific board. All I could find are the R418 and the Version 2 board specs from stason.org. And I can't get this thing to POST properly. It did went through the detection of memory, floppy drives, hard drives, etc. just fine. But just before booting into an OS, it freezes. Now, I'm assuming that the CPU settings on this board are set wrong considering that I don't know the specific CPU settings for this board. The CPU I'm using is an AMD AM5x86 133mhz processor. Does anyone happen to have the manual for this specific board or at least the jumper instructions for the CPU? Any help is greatly appreciated.

Last edited by DoomGuy II on 2014-12-27, 01:10. Edited 1 time in total.

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Reply 1 of 8, by Anonymous Coward

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I think R418W2 is version 2. Don't the jumpers line up? I have the same board and I used the version 2 docs.

"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium

Reply 2 of 8, by feipoa

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From my recollection, forum user Anonymous Coward was eventually able to setup this motherboard without issue. You may want to contact him. He was also successful in making the custom PS/2 mouse modification work on this board. If interested, more on that here: Native PS/2 mouse implementation for 386/486 boards using the keyboard controller

Ultimate 486 Benchmark | Ultimate 686 Benchmark | Cyrix 5x86 Enhancements | 486 Overkill Graphics | Worlds Fastest 486

Reply 3 of 8, by feipoa

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by Anonymous Coward » 2014-12-26 @ 16:59
by feipoa » 2014-12-26 @ 17:01

I guess he beat me to it.

Ultimate 486 Benchmark | Ultimate 686 Benchmark | Cyrix 5x86 Enhancements | 486 Overkill Graphics | Worlds Fastest 486

Reply 4 of 8, by DoomGuy II

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Well... turns out that the external cache was set incorrectly. I was actually able to get this thing up and running now. Yay! 😁

Looking for vintage computers and parts. PM me if you have some to give away.

Reply 5 of 8, by Anonymous Coward

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There are some undocumented FSB settings on this board. It can do 60MHz and I think 66MHz as well...but I don't believe the signal is very clean. I have no had good luck with am5x86 at 180 (3x60) or cx5x86 at 120 (2x60).

I also recommend running the award BIOS rather than AMI if that's what you have installed.

"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium

Reply 6 of 8, by bbuchholtz

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Anonymous Coward wrote on 2014-12-27, 09:24:

There are some undocumented FSB settings on this board. It can do 60MHz and I think 66MHz as well...but I don't believe the signal is very clean. I have no had good luck with am5x86 at 180 (3x60) or cx5x86 at 120 (2x60).

I also recommend running the award BIOS rather than AMI if that's what you have installed.

Just curious - how did you go about accessing the undocumented FSB settings? I see a place where an additional jumper could be soldered on, beneath the FSB jumpers.

Also, how do you configure the PCI divider? Is that automagically handled by the FSB jumper settings? I didn't see anything in the BIOS. Just ISA-related settings. Basically, I want to use a 40MHz FSB, and lock the PCI bus at 33MHz. Or does this not work with bus mastering?

-Brian

Reply 7 of 8, by Anonymous Coward

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UNDOCUMENTED 60MHz setting:
JP38 - Open
JP39 - Short
JP40 - Short.

The PCI divider is NOT handled by the BIOS. There is a jumper dedicated to that. It's a 1/2 divider. There is no support for other dividers.

JP25 -- PCI bus clock speed --
1-2 => PCI bus clock = system clock
2-3 => PCI bus clock = 1/2 system clock

"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium