Re: The 486 I swore I'd never build.

Posted on 2023-09-20, 04:12

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by jakethompson1

in Marvin \ System Specs

in Marvin \ System Specs

Anonymous Coward wrote on 2023-09-20, 02:44: Cache performance should be fine as long as you don't enable write back. Unless someone has run into convincing evidence otherwise, I believe both the UM481 and UM491 run L2 cache as either write-back or disabled. There is no write-through on these …

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Re: The 486 I swore I'd never build.

Posted on 2023-09-19, 20:34

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by jakethompson1

in Marvin \ System Specs

in Marvin \ System Specs

Looks good. I think your SARC chipset is actually a relabeled UM491 which is the same I used in the test above. However there is another piece. Notice the empty SRAM socket on your board. That is presumably for dirty RAM and left empty to save money. The cache performs better with that fitted for …

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Re: The 486 I swore I'd never build.

Posted on 2023-09-19, 14:37

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by jakethompson1

in Marvin \ System Specs

in Marvin \ System Specs

Definitely some additional wait states and such as hidden settings (use amisetup)

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Re: The 486 I swore I'd never build.

Posted on 2023-09-19, 04:49

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by jakethompson1

in Marvin \ System Specs

in Marvin \ System Specs

I have no clue what "Hard Disk Type 47 RAM Area" could possibly be, nor "Memory Remapping", "F Segment Shadow RAM", "E Segment Shadow RAM" or any of the disabled "Non-Cacheable BlockX" settings. I have a copy of Programmer's Guide to the AMIBIOS and have looked at a bunch of these so here goes. …

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Re: Setting the L2 to WT instead of WB, CY5x86

Posted on 2023-09-18, 22:29

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I think you are mixing up write-back internal cache (L1) and write-back external cache (L2) The internal cache can cache the whole 4GB range. It is the external cache that is set up such that 32MB can be cached by a 256KB cache and 7-bit tag. Write-back versus write-through cache is controlled by a …

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Re: M919 DMA on Windows 98SE

Posted on 2023-09-18, 19:17

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The UM8886BF has the bit set in its PCI configuration space as if it supports bus mastering, but it doesn't support the Intel Triton-compatible PCI Bus Master IDE Controller specification described here: https://pdos.csail.mit.edu/6.828/2018/readings/hardware/IDE-BusMaster.pdf which is what the DMA …

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Re: Which one of theese Pentium 1 motherboards would you recommend me to buy?

Posted on 2023-09-17, 19:31

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Mmmm.... so guys, I was a little undecided / confused, so I made a chart to summarize all your useful info and suggestions: https://i.imgur.com/RGn90Pk.png So, with the votes the answer seems pretty obvious. But there's the case problem: I really wanna use that old AT case. For your convenience, …

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Re: Which one of theese Pentium 1 motherboards would you recommend me to buy?

Posted on 2023-09-16, 00:55

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

My immediate view (and I am not an expert like others here) would be in favour of the second board - i) it's ATX, ii) it uses a standard CR2032-type clock battery, iii) it's full of Intel-branded things, iv) SDRAM support. I was going to say that I assumed MSI still had drivers/BIOSes/etc for it, …

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Re: Which one of theese Pentium 1 motherboards would you recommend me to buy?

Posted on 2023-09-16, 00:20

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I think I've read some newer ATX cases don't have mounting points for BAT boards anymore, but I haven't had much experience with modern ATX cases and haven't run into that myself. Beyond no drive bays the bigger issue for me is some of the newer cases can't take a board as wide as a typical Baby AT …

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Re: Kingston KTM-AT memory expansion board

Posted on 2023-09-14, 22:52

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You don't want ISA memory expansion boards in a 386 except as a last resort for performance reasons

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Re: Need Help with Quadtel BIOS for My Emerson 500EC...

Posted on 2023-09-14, 14:10

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I think you can suppress the security system with these changes. odd, offset 0x1BE06, change 0x00 to 0x01 odd, offset 0x1D106, change 0x1A to 0x90 even,offset 0x1D106, change 0x75 to 0x90 even,offset 0x1D113, change 0x74 to 0xEB

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Re: List of VLB IDE Controllers

Posted on 2023-09-12, 03:21

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Weird. I've never seen that before. I looked through DOS/CMD640X.SYS with a hex editor and didn't see that string in it anywhere, but I guess it could have been obfuscated. It does light up a lot of warnings on virustotal. I checked the raw disk image and it produces the same warnings, so I'm glad …

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Re: VLB with newer chipsets

Posted on 2023-09-10, 17:47

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Designed for Windows 95 AMD chip, anyone? Surely that means AMD is better than Intel, right? That AMD 5x86 socket 3, 486 class chip -- I wonder if that would be installed in a fully compliant PNP BIOS motherboard... I always figured AMD got the Designed for Windows 95 logo so as to help counteract …

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Re: VLB with newer chipsets

Posted on 2023-09-10, 02:58

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I'm not the best judge of that stuff as, when I first have to use a Windows system, the first thing I do is revert as many of the UI changes since Win95 as possible. So the more terribly specced the typical Windows system is, the better for me, because the faster it operates when the new junk is …

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Re: VLB with newer chipsets

Posted on 2023-09-10, 02:12

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Anyone know if the "Designed for Windows 95" logo program required a PCI bus? most likely no, I do know that Windows logo required APIC https://community.osr.com/discussion/21604 and that would limit you to intel chipset 486, but still cover EISA/ISA. APIC required in 1995? no way. I think that is …

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Re: Tips for building (or starting to build) a retro DOS/98/XP PC under a $100 budget?

Posted on 2023-09-10, 01:29

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

For 98SE, would a K8V-MX be a good motherboard? Let's see what others more knowledgeable than me have to say, but at first glance, seems reasonable - VIA chipset, Asus has 98SE drivers for it on their web site, AGP, 2 PATA channels (and SATA). I was going to say the same thing. It's newer than …

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Re: VLB with newer chipsets

Posted on 2023-09-10, 00:59

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Licensing is a non issue, PCI-SIG had ~same annual payments as VESA. Bios is fixed cost. Afaik slot is the same reused MCA molding as in VLB. What did cost was newer chipsets. I don't know how BIOS licensing costs worked--did AMI, Award, Phoenix license a BIOS for some old chipset like UM481 for a …

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Re: VLB with newer chipsets

Posted on 2023-09-10, 00:53

by

by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Anyone know if the "Designed for Windows 95" logo program required a PCI bus?

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Re: Missing conventional memory

Posted on 2023-09-09, 20:43

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by jakethompson1

in Marvin \ Software

in Marvin \ Software

It is a setting called "PCI IDE BUSMASTER" in the bios menu. I have only seen it on AMI bioses, never on an Award bios. When you enable it, DMA mode is enabled on the onboard ide controller on the 430FX chipset. I don't think many people realize or know about this feature. It means in realmode dos …

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Re: VLB with newer chipsets

Posted on 2023-09-09, 20:26

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by jakethompson1

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

From a technical standpoint VLB was super crap. The cards have to be very long. That makes them (more) expensive to produce. Fitting them required a lot of force. And you have a lot more pins than ISA or PCI that have to make perfect contact. I can fully understand that nobody wanted it as soon as …

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