Re: Matrox Impression IS-Athena

Posted on Yesterday, 12:11

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You need to run the SetVGA.exe tool, and the video bios needs to be shadowed in BIOS or through Rambios.sys. "setvga -m2", or if it doesn't work "setvga -m1". SetVGA is in the Dos drivers: https://ftp.matrox.com/pub/mga/othermga/previous/1552_164.zip from here: https://video.matrox.com/en/apps/ …

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Re: Intel 486DX4-100 @ 120MHz ?

Posted on Yesterday, 11:48

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

My notes say a DX4 @ 120 has the integer performance of a Pod83, and the floating point performance of a Am5x86 (133). So it's worth it if true. This is the schematic for the Voltage Regulator: https://www.alldatasheet.com/html-pdf/42419/SEMTECH/EZ1085CT/751/3/EZ1085CT.html The two or three …

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Re: Intel 486DX4-100 @ 120MHz ?

Posted on 2025-04-16, 12:27

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

If you have the part number for the voltage regulator on the interposer, then it can be calculated what to change to increase voltage, and solder on either different resistors or regulator.

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Re: 3d modelling Win 3.1?

Posted on 2025-04-14, 12:58

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The back of the box on the Matrox Impression Plus 220 (ISA 2D/3D accelerator card) says: DynaView DOS, AutoCAD R11, R12, Microstation 4.0 & 5.0, 3D Studio, CADKey

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Re: 386SX pin-compatible upgrades

Posted on 2025-04-13, 13:47

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

There's delays or extra clocks added once the BIOS recognises the 486SLC chip, from what I can tell. This Chips 82C836 board had fast memory speed with a 386sx@25Mhz 0WS, but now need to run the system clock all the way up to 40-50Mhz to get similar speeds again. ~20-22MB/s. The ALI M1217 board …

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Re: Chips&Technologies CT-64300/301 VLB Card found, interesting results.

Posted on 2025-04-11, 11:56

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

It should fly in windows 3.1/95 tests too compared to the 5428

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Re: Help Request: Max CPU upgrade on Biostar M6TBA Ver. 1.4

Posted on 2025-04-11, 11:45

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Don't know if you've seen this... https://en.wikipedia.org/wiki/List_of_Intel_P … _III_processors This lays out all P3 compatible CPUs... Tualatins have more L2 cache which is a big boost. Katmai L2 cache runs at 50% clock speed, whereas Coppermine & Tualatin run at full speed.

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Re: Why do PC manufacturer's use lower end/limiting chipsets?

Posted on 2025-04-06, 10:08

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

CPUs are binned into seperate models because the silicon doesn't always turn out perfect. Onboard cache & CPU speed is tested. As well as chipsets / motherboards having low end versions to make the whole system cheaper. The main price points target 1) Businesses looking for high priced tax write- …

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Re: 386 not working?

Posted on 2025-04-05, 17:52

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

If the BIOS checksum is not completing, try reseating the BIOS (and other removable ICs) and/or cleaning legs with isopropyl alcohol & a toothbrush. They build up oxidisation and don't contact well over time.

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Re: Seminal machines in a given class: Turbo XT+EGA, 286+EGA, 286+VGA, etc. - the machine vs. the era

Posted on 2025-03-30, 09:10

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by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The Amstrad Mega PC was a 386sx + cache + a 16-bit 486 CPU... which is the cost-optimised option for running 16-bit high performance 2D games. You could spend $500-1000 more on a 32-bit 486 and have the same performance in those 2D games, but have an upgrade future... The Amstrads always had been …

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Re: Necessity of TCK, TDI, TDO, TMS pins on Am5x86 and Cx5x86 CPUs?

Posted on 2025-03-30, 08:12

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

One other issue was that CLKMUL isn't wired, but I don't mind jumpering just one pin. On some CPUs R17 is not connected, or connected to B13 instead. Such as AMD DX2 & DX4 (non WB) CPUs. On other CPUs R17 is CLKMUL, and B13 is WB/WT select... AM5x86, Cyrix 586, Intel DX4, AMD DX2 & DX4 (WB). From …

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Re: Seminal machines in a given class: Turbo XT+EGA, 286+EGA, 286+VGA, etc. - the machine vs. the era

Posted on 2025-03-30, 08:00

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

In the mid 90's when 486's came out, a second hand 386sx which only needed to run Win 3.1 and business software was hard to pass up. Somebody may have gotten by on an uber 286 and Win 2.1, but if there's specific programs you need that only worked on Win 3.1 then the low cost option was a 386sx. The …

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Re: Difference between DX2 and overdrive

Posted on 2025-03-28, 11:32

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by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Does the DX2ODPR66 also have 16KB L1 cache or was that only reserved for the DX4 Overdrive? The DX2ODPR66 only has 8KB L1 cache. The marketing was aimed at 486SX owners which had no heatsink & fan, so I believe the heatsink was provided so the user didn't mess up putting a heatsink on and then …

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Re: What are the 3 best 486 motherboards?

Posted on 2025-03-28, 11:21

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by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The best 486 + VLB motherboard is the ASUS VLI-486SVGO/486SV2GX4. The X4 has the voltage regulator for DX4 cpus. SIS 85C471/407 chipset, 1024KB L2 cache, CR2032 coin battery, PS/2 mouse header, BIOS supports Enhanced IDE.

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Re: Difference between DX2 and overdrive

Posted on 2025-03-25, 14:51

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Intel DX4 ODP/ODPR100 have 16KB L1 cache I don't have the ODP/ODPR66's but the multiplier is labelled undefined in the manual for the 3x position. Low = 2x (default). High = 3x (DX4 CPUs). Not to say that it definitely won't work on all CPUs.

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Re: DX4ODPR100 fan recommendation?

Posted on 2025-03-22, 14:44

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

If you use a 40x10mm fan, you can secure it with two long screws through the standard heatsink

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Re: DX4ODPR100 fan recommendation?

Posted on 2025-03-21, 13:06

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

It doesn't run cool but a weak fan will work. I bought an ODPR-100 with heat damage not too long ago. 3dBench runs but with mixed up polygons, most programs fail to load. But at 75Mhz it runs perfect. I bought a second ODP-100 and put a 40mm fan on it. Need to make a custom connection to what you …

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Re: Wow ISA BUS insanely overclocked and running DOOM at 35 FPS with an ISA ATI Mach32

Posted on 2025-03-20, 14:18

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Bizzarely fast RAM speed on that UMC board. Looks like it was tuned to fully utilise EDO DRAM. And you're right about the CL-GD5402/24/29 being similar to the CL-GD5434. A lot of 486 boards are going to have slow memory speed. I work with mostly 386SX & DX so memory speed is always on the floor. …

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Re: How to enable clock-doubling on Ti 486SXL2 CPUs

Posted on 2025-03-19, 14:57

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Did you solder it using a hot air gun or soldering iron? I believe CD'd doesn't work in the 386sx (TI486SXLC2) when you use a hot air gun to solder the CPU. The max temp in the manual for the TX486SXLC2-G50-WN (most common version available) is 85C. It's unclear if this includes non-operating …

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Re: Wow ISA BUS insanely overclocked and running DOOM at 35 FPS with an ISA ATI Mach32

Posted on 2025-03-18, 13:10

by

by MikeSG

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Mike, pass a visual reference for your board. I remember you mention it in the SXL2 interposer thread but still don't know which one it is. Or if you posted somewhere in the thread there i either didn't see or forgot about it. I have almost 0 experience with 386SX stuff, other than 2-3 boards like …

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