Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-29, 12:22

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I too have had few complaints w.r.t UMC's handling of PCI w/486 motherboards. For years I have been using a 3-slot PCI UMC-based 486 with PCI graphics, PCI SCSI, and PCI networking (Matrox G200, Adaptec 2940U2W, 3Com 3c905-TX-M 10/100Base-TX, respectively) in Windows NT 4.0 without incident. The …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-18, 23:49

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I am generally inclined to agree with Tetrium. I have had a 486 motherboard with 3 VLB slots (no PCI), 4 72-pin SIMM slots, and a working PS/2 mouse port. It was the only PS/2 mouse capable non-PCI 486 motherboard I had ever seen. I'm sorry now that I let it go. I did not try EDO RAM in it, nor did …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-18, 20:22

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

PC Chips M919 has a single VLB slot, 3 PCI slots, and supports EDO. v3.4 has a fairly recent BIOS -- May or June 1996. I use this MB on my testbed.

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Re: PS/2 6 pin cable - are they hard to find?

Posted on 2011-03-14, 22:49

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

@Tetrium I purchased one of those KVM units (Belkin-F1D102) on eBay for cheap and will test the PS/2-to-RS232 emulation method they use once it comes in the mail. I will compare it against that used by the Vetra Systems emulators. In response to someone another comment, I do not believe it is …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-14, 14:46

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks for the tip. I'll test the 66 Mhz, 2x, 1:1/2 trick out on my MB-8433UUD and M919 using some less-rare cpu first. L2 is all 15 ns. From what I remember reading some time ago, if the UM8881F chipset has an E, as shown below in the given location of -EYT, then it supports EDO RAM. UM8881F 9633- …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-14, 04:39

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

udam_u, could you also post what other BIOS settings were required for operation at a 50 Mhz FSB on your Cyrix 5x86-150? I didn't see it in the other post. I briefly attempted this at 5V and 50 Mhz FSB but didn't get past memory check on my M919 w/128MB EDO RAM. It went to about 109,000 KB and froze …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-14, 03:41

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

How would you overclock a Cyrix 5x86-120 to 133 Mhz that has a 3x multiplier? I can see using 50 Mhz FSB and a Host-PCI clock division of 2:3 for 150 Mhz. But I doubt the Cyrix 5x86-120 would be stable in Windows with 30 Mhz of extra boost. I will try it on my Biostar MB-8433UUD v3.0 and M919 v3.4 …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-13, 19:01

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I have several Cyrix 5x86 chips, none of which have the 4x multiplier 2x Cyrix 5x86-120 1x Cyrix 5x86-100 2x IBM 5x86-100HF in a Gainberry upgrade marked as 120 Mhz I wish there was an easy way to short, or add some diode or resistor to force these into 4x mode. Maybe there is. Does anyone have a …

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Re: 486 mobo + 586 chip

Posted on 2011-03-12, 08:21

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

What does your 486 case look like? I doubt you can get still get this on. Its pretty modern looking for a 486 case. There isn't a model number on it. I bought it new in Jan. 1997 with my 486. I am also looking for another case for my second 486, the m919 I have setup on the table. Unfortunately for …

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Re: Fastest PCI graphics card in a 486

Posted on 2011-03-11, 23:54

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

If you look at the far left of the chip, there is a vertical part number in white. All the M919 cache modules that have been posted so far say M919-0153. I've tried several early model P1 COASTS, none work except for the M919 SRAM modules.

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Re: 486 mobo + 586 chip

Posted on 2011-03-11, 21:15

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thought I'd post the face to those specs.

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Re: Fastest PCI graphics card in a 486

Posted on 2011-03-11, 20:25

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Regro Games, regarding that post, I think you have a winner. Try setting the L2 to Write-Back, power down, remove cache, power up, power down, reinsert cache, power up, resave BIOS such that L2: Write Back and check Cachechk and Speedsys again. With my other cache module (the more flakey one), this …

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Re: Fastest PCI graphics card in a 486

Posted on 2011-03-11, 20:19

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I noticed significant speed improvement with everyday office tasks when I inserted the 256 KB cache module. It was a real eye opener for me. I'd never want to use this board without cache again. Surprisingly, I've found some of the cache modules work better than others. On some of them, they …

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Re: Fastest PCI graphics card in a 486

Posted on 2011-03-11, 09:48

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The M919 that I bought new at a computer store in 1997 did not come with the cache module. However, I later found the cache module on eBay in about 2000. It was hard to distinguish them between the Pentium-based COAST modules, which will not work in an M919. The auctions still call them COAST …

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Re: 256AK vs 257AK Cache

Posted on 2011-03-09, 05:19

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Are you speculating or do you know this from past research or experience? ISSI and Alliance also use *256 notation. I am puzzled one company would take the oddball part number approach. Winbond's 64K chips read *512, which makes sense, not 513 or 514. I have the spec sheet for the W24257AK-15 chip …

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256AK vs 257AK Cache

Posted on 2011-03-09, 02:22

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Does anyone know what the difference between 486 cache (2 rows of 14 pins) that is marked as *256AK-15 vs. that marked *257AK-15? I have, for example, cache with markings: UM61256AK-15 And some as: W24257AK-15 I am inclined to think that that the *257 contains an extra Kilobit. Any ideas why? Is it …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-09, 01:39

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by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Yes, for the announcement that was on cpu-world. I cannot find it. If it was a non-public announcement, can you let me know which admin you are referring to? Thanks.

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Re: Fastest PCI graphics card in a 486

Posted on 2011-03-09, 01:36

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I ask because my Diamond Stealth 64 VLB (4MB) receives a significantly higher pcpbench score over my Matrox Millennium G200 PCI (16MB) card at a 40 Mhz fsb and a Cyrix 5x86 -120 cpu. PcpBench: Diamond Stealth 64 VLB score was 9.7 Matrox Millennium G200 PCI score was 7.6 PcChips M919 motherboard with …

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Re: UMC chipset PCI 486 mobo. AMD P90 CPU options?

Posted on 2011-03-09, 00:00

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Can you post the link to this past group buy? I am having trouble finding it on cpu-world.

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Re: 486 mobo + 586 chip

Posted on 2011-03-08, 23:09

by

by feipoa

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Windows NT 4.0 will crash during boot at 1:1 with a 40 Mhz FSB and a Cyrix 5x86. I have not yet isolated exactly what is causing the crash. It may be that the Matrox G200, Adaptec Ultra2 SCSI, or the 3Com 3c905C-TX-M PCI card refuses to run at 40 Mhz, or a combination of these and particular Bios …

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