Re: BIOS image collection - requests, discussion etc

Posted on 2019-08-24, 08:06

by

by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

What to do when I have a different BIOS for already catalogged motherboard ? I would think the better idea is to add the new BIOS to the post of that mobo rather than make another entry with the new BIOS.

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Re: Picking a sound card for a low-end 486

Posted on 2019-08-24, 07:11

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by Tiido

in Marvin \ Sound

in Marvin \ Sound

ALLOYRUN.RAD is definitely already showing that the Crystal chip is not doing what Yamaha is. The snares have a metallic tone in them while OPL3L shows pretty much just noise. That shows the modulation index isn't going high enough on the crystal chip. Doom track has the cymbals all having different …

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Re: What retro activity did you get up to today?

Posted on 2019-08-23, 18:33

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I added gameport disabling feature to an IO card I got today, tested couple of my motherboards with strange results and found that one 400something MB HDD I have seems to have gone bad (BIOSes wait for it to spin up, despite it having done so already). Also replaced a dumb WinBIOS with a MR BIOS on …

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Re: Bought these (retro) hardware today

Posted on 2019-08-23, 14:12

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

New toy, I cleaned it up and set jumpers right for my needs. Now to actually test it.

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Re: Legit Harris 25MHz?

Posted on 2019-08-23, 11:09

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The UTsource chip I bought and it definitely looks like the real deal. Passed acetone test and performs properly too. HT12A definitely won't do 25MHz but it gets to 20MHz no problem but few extra MHz and it starts to crap out. on the board i have there's two oscillators, both go to chipset but one …

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Re: Picking a sound card for a low-end 486

Posted on 2019-08-23, 07:15

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by Tiido

in Marvin \ Sound

in Marvin \ Sound

I'm most familiar with the main theme of Supaplex, it is a nice track but unfortunately not a very good test track since it doesn't use sounds that would show up more subtler differences. You could perhaps use the same track as was in the video shown earlier that compared various sound cards. …

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Re: Picking a sound card for a low-end 486

Posted on 2019-08-23, 04:10

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by Tiido

in Marvin \ Sound

in Marvin \ Sound

Perhaps not an all in one part then, but the WSS part of the YMF71x is near identical clone of CS4231, the datashit even says so and I have personally verified it to be the case. Even the ID bytes are same and a bug of CS4231 is there also (upper and lower bytes get swapped in a WSS 16bit DMA …

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Re: Motherboard not detecting L2 Cache

Posted on 2019-08-22, 17:14

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

TAG RAM is probably normal 32K x 8 chip like the other chips so you'll need 9x same type chips. If there was damage you'd know it already.

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Re: Motherboard not detecting L2 Cache

Posted on 2019-08-22, 16:54

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

"pentium", that's the cruciual info I have managed to miss... Pentiums have 64bit databus which means all the cache sockets must be filled (each chip is 8 bits).

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Re: Picking a sound card for a low-end 486

Posted on 2019-08-22, 07:00

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by Tiido

in Marvin \ Sound

in Marvin \ Sound

Could be 4235, I remember one of them was outright broken while others were ok. I don't have a CS4289 card to test stuff with but I would think it makes sense that it is same as original YMF289 given the same pinout and that there was some sort of deal between Crystal and Yamaha as far as CS4231 and …

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Re: Samtron SM-470 help - info needed!

Posted on 2019-08-22, 05:43

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by Tiido

in Marvin \ Video

in Marvin \ Video

It seems it justs uses non standard weighting on the RGB mixer, it is a matter or resistor choices in the mixing circuit and likely just uses normal E12 series parts there rather than tries to get the correct luminance mix. It probably isn't difficult to figure out the weighting ratios that produce …

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Re: Motherboard not detecting L2 Cache

Posted on 2019-08-22, 05:35

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I think the chips need to be in every other socket

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Re: Picking a sound card for a low-end 486

Posted on 2019-08-22, 05:00

by

by Tiido

in Marvin \ Sound

in Marvin \ Sound

That video shows only the horribly broken CS4236 all-in-one chip which came later out of Crystal stuff. Other crystal all-in-one chips in the same line (5, 7, 8, 9) are nowhere near as broken, and they are still not the stand alone FM chip that is being discussed here. Crystal I think licensed …

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Re: Motherboard not detecting L2 Cache

Posted on 2019-08-22, 03:45

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Did you also fill the TAG RAM socket ? The tiny photo only shows 8 sockets but there's a 9th one somewhere too that must be filled.

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Re: Can my Amiga 3000 be saved from evil battery?

Posted on 2019-08-21, 16:17

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

This looks fairly mild and definitely nowhere near to a point where repairs aren't gonna be worth it. That battery should be removed immediately, wiggle it until it comes off if you cannot desolder it. Vinegar is used to neutralize the acid residues, isopropanol or other cleaning alcohol to clean up …

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Re: ISA card doesn't fit in slot - are non-standard ISA cards a common occurence?

Posted on 2019-08-21, 14:04

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by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I have filed off a little bit of the rearmost edge that goes in the slot to reduce the stress. But I first just loosen motherboard screws while cards are in, wiggle stuff into the best possible alighnment and tighten the screws again.

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Re: Can Display port to vga adapter output 160Hz on Diamond Pro 2070SB Crt ?

Posted on 2019-08-20, 09:36

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by Tiido

in Marvin \ Video

in Marvin \ Video

You're only gonna get 160Hz in fairly low resolutions (1024x768 and less), both due to monitor and any converter limitations. Cheap converters pretty much top out at 1920x1080 at 60Hz or other similar spec.

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Re: Newly made 4MB 30pin SIMMs

Posted on 2019-08-20, 07:59

by

by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I'm not sure when new PCBs get ordered, these things are going lot slower than I hoped. I don't have anything against selling blank PCBs though, but they'll certainly cost more than one making their own and ordering them themselves. SDRAM (that includes DDR and all newer things) quantify their …

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Re: Bought these (retro) hardware today

Posted on 2019-08-20, 04:59

by

by Tiido

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

This is the very last Yamaha YMF71x model that uses the ISA bus. ... The very last is YMF741, but I don't know what the difference is. anyway YMF711 is same as YMF718 (OPL3-SA2) and YMF715 is same as YMF719 (OPL3-SA3), there's no letter version, B, E and F versions out there. 711/718 adds PnP and …

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Re: Picking a sound card for a low-end 486

Posted on 2019-08-19, 12:56

by

by Tiido

in Marvin \ Sound

in Marvin \ Sound

I have an UMC based board that acts strange too, though in form of general instability.

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