Re: Opti 82C391: Is there a DOS configuration utility for memory timings?

Posted on 2021-11-28, 18:25

by

by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I am not sure if slow refresh and hidden refresh are mutually exclusive. They are not mutually exclusive. Slow refresh is about how often the RAM gets refreshed. Usually "slow refresh" means that three of four refresh cycles are skipped. Most standard PC RAM is not specified for slow refresh, so …

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Re: Opti 82C391: Is there a DOS configuration utility for memory timings?

Posted on 2021-11-28, 15:57

by

by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

CTCHIP34 does work on my CT-386-33A/40A motherboard. The BIOS default was CAS 4 for memory reads and CAS 3 for memory writes. Slow refresh was not enabled, but hidden refresh was. The best I could get was CAS 3 for both memory reades and writes and enable slow refresh. I am not sure if slow refresh …

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Re: Opti 82C391: Is there a DOS configuration utility for memory timings?

Posted on 2021-11-27, 17:22

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

https://www.vogons.org/viewtopic.php?f=46&t=66506 I had quite a trouble to get to know what chipset this board has, but found it out - it's the same you care about. As you can read from the thread, there's MR BIOS available for your chipset. It has some memory timing settings available too. ;) …

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Re: Opti 82C391: Is there a DOS configuration utility for memory timings?

Posted on 2021-11-27, 17:07

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

maxtherabbit wrote on 2021-11-27, 16:35: I don't know if it's supported offhand, but check out CTCHIP34 The Opti 82C391 is supported in the list of configuration files in CTCHIP34 and there are settings for read and write wait states. I will give this a try and see how it goes. Thanks for the heads …

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Opti 82C391: Is there a DOS configuration utility for memory timings?

Posted on 2021-11-27, 16:27

by

by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I have a CH-386-33A/40A motherboard with an Opti 82C391 chipset. The BIOS lacks any settings for memory timings. Is there a DOS configuration utility that exists to do this?

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Re: 386DX/40: How far can I take this?

Posted on 2021-11-27, 05:38

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The 5v version of the cpu had a 50mhz part. My impression is that most of the 40mhz parts run at 50 without issue. Does the Mx chipset support 50mhz? Unfortunately I have been unable to find any datasheets on the Mx chipset in question. Macronix is still in business, so I emailed them looking for …

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Re: 386DX/40: How far can I take this?

Posted on 2021-11-27, 02:24

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

There's not a lot more you can do with this system. Your SXL-40 actually supports clock doubling just like the SXL2. But it doesn't help you much if you want a 33 or 40MHz bus. These 5V SXL chips top out around 55MHz if you're lucky. You probably could get it to run at 50 with a heatsink though. …

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386DX/40: How far can I take this?

Posted on 2021-11-27, 00:09

by

by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I pose that question in the title of this post because that is exactly what I asked myself the first day I got this computer in November 2020. I did set one limit on this in that there would be no modifications to the motherboard itself. The motherboard is a Biostar MB-1340MKA-F with a MACRONIX …

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Tandy 1000 TX dual monitor setup TGA + Hercules

Posted on 2021-11-21, 03:18

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by jasa1063

in Marvin \ Video

in Marvin \ Video

I decided to see how well a dual monitor setup with a Hercules graphics card would work in my Tandy 1000 TX. I am glad to say all worked well with no surprises. Setting motherboard dip switch 1 on will make the onboard TGA the primary and setting it off will make the Hercules card the primary video. …

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Re: Multi I/O card identification

Posted on 2021-11-17, 03:38

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I am having trouble finding the jumper settings for this Multi I/O card. I found a PM540 on stason.org, but this is a PM540 G. Any help would be appreciated:) https://www.elhvb.com/iocard/PM540G.txt https://stason.org/TULARC/pc/hard-disk-floppy-controllers/U-Z/UNIDENTIFIED-Two-IDE-AT-Interface- …

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Multi I/O card identification

Posted on 2021-11-17, 03:10

by

by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I am having trouble finding the jumper settings for this Multi I/O card. I found a PM540 on stason.org, but this is a PM540 G. Any help would be appreciated:)

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Re: Northgate 386DX/25 w/Omnikey 102 keyboard

Posted on 2021-11-16, 01:45

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Wow, your timing was perfect, those keyboards sold out FAST once they were put in the store, I think we had one left in the back room that just went last week out of a batch of 4-5 that were donated. Are you also on the FGTC Discord or was it random luck that you happened in at the right time? …

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Re: Northgate 386DX/25 w/Omnikey 102 keyboard

Posted on 2021-11-14, 18:58

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

A few more pictures.

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Northgate 386DX/25 w/Omnikey 102 keyboard

Posted on 2021-11-14, 18:57

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I lived in Bloomington, MN from 1988-2011. There was a Northgate computer outlet store just a few miles down the road from me. My first 386 computer was a Northgate 386DX/20 I got in 1990. I have always wanted to recreate the experience of having a Northgate 386 and matching Omnikey keyboard. I got …

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Re: XT-IDE on an AT clone: should this work?

Posted on 2021-11-14, 01:27

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I have run a XTIDE with a compact flash on a 386sx with no problem. Both through a Blue Lava Systems XTIDE adapter with built in Compact Flash and using an XTIDE BIOS and a regular IDE internface. I had no problems with either one.

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Re: Northgate Omnikey 102 missing badge replacement

Posted on 2021-11-14, 01:08

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I reached out to Robert Tibbetts who is well known for his repairing of Northgate Omnikey keyboards. He was able to supply me with a reproduction label that I just had to trim to fit the my Northgate Omnikey 102 keyboard. Here is the result.

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AST Adventure! Advantage 6060P Socket 4 System w/Pentium Overdrive 133 (PODP5V133)

Posted on 2021-11-13, 17:01

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Earlier this year I made a Craigslist purchase for what I thought was going to be a 486 Pentium Overdrive 83MHz (PODP5V83). When I finally met the gentleman, what he had was a Pentium Overdrive 120/133 for a Socket 4 (PODP5V133). The asking price was only $15 so I made out much better than I thought …

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Northgate Omnikey 102 missing badge replacement

Posted on 2021-11-01, 03:22

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by jasa1063

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I was lucky enough to a Northgate Omnikey 102 keyboard in really good condition, but the Northgate logo badge is missing. Does anyone know a source for a replacement?

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Re: ATI VGA Wonder XL24 stuck at 640x480

Posted on 2021-10-17, 20:11

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by jasa1063

in Marvin \ Video

in Marvin \ Video

I did some further testing on the computer that is having issues. On initial power on, it is not detecting the monitor properly. Doing CTRL+ALT+Delete and after that reboot the monitor is recognized properly and all video modes are available again. I am still doing more testing, but at least I have …

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Re: ATI VGA Wonder XL24 stuck at 640x480

Posted on 2021-10-17, 16:38

by

by jasa1063

in Marvin \ Video

in Marvin \ Video

I tried in a different computer with an HP 17" LCD and what do you, it's now working!

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