Re: The Soundblaster DSP project

Posted on 2024-01-26, 03:53

by

by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Just replaced the bugged DSP on one of my SB16 cards (CT2910) with Maelgrum's latest release burned to an AT89C52. Great stuff! Initial tests indicate that digital audio and FM is working properly, but I wasn't able to test MIDI yet since I didn't have my SC-55 at hand. So I wanted to ask, knowing …

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Re: Varta replacer

Posted on 2024-01-26, 03:43

by

by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Yeah, whenever possible disabling the charging circuit is a much better option if you're trying to use a CR2032. Not only a coin cell provides a lower voltage (3V) than the original barrel (3.6V) but also the extra diode you add will lower that voltage even further, which can result in the battery …

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Re: Confirm a question about this forum

Posted on 2024-01-26, 03:37

by

by TheMobRules

in Milliways

in Milliways

I get the impression that many people spend more time collecting and working on hardware than playing games. I think people get a dopamine hit from finding rare computers or parts. It's like a treasure hunt! I think it's more due to stuff like DOSBox and SCUMMVM reaching a level of maturity that …

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Re: Dead 486! Anyone able to repair what I can't?

Posted on 2024-01-26, 03:25

by

by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I'm nowhere near the US so I cannot offer to attempt a fix, but one thing you should consider is getting a PCI/ISA POST card on eBay (they're very cheap). It will let you know whether the CPU is trying to execute BIOS code, which is an important first step when troubleshooting a board.

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Re: Bought these (retro) hardware today

Posted on 2024-01-26, 03:15

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

i found this on ebay and thought it looked interesting. i can't find many references to this card on the internet or here on vogons. a new orchid kelvin mpeg vlb. it has a cirrus logic gd5434 along with a em7000 mpeg-1 decoder all on the same board. Very nice! I knew about the regular Kelvin-64 …

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Re: Getting a little annoyed by CF card spam, am I alone?

Posted on 2024-01-25, 05:50

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by TheMobRules

in Milliways

in Milliways

One more thing, I recall an RMC video where he went through multiple Amiga 500 external hard drives and they were all working if I recall but he didn't keep one of them with an original drive and replaced them all with CF because "they're gonna die soon" or something to that effect. Again like …

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Re: AT (Clone) - Motherboard Formfactor

Posted on 2024-01-24, 04:46

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

It's OK, the 4MB are being detected correctly. What happens is that the first MB of memory is divided as: 640KB (Conventional Memory) and 384KB (Upper Memory Area). The remaining 3072KB are used as extended memory. The Upper Memory Area (UMA) is used for things like mapping video memory and …

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Re: Getting a little annoyed by CF card spam, am I alone?

Posted on 2024-01-23, 20:46

by

by TheMobRules

in Milliways

in Milliways

Yeah, I'm on the spinning HDD team as well, they give so much of that authentic retro feel I seek, just like CRTs vs LCDs. But that's maybe because I have accumulated quite a few of them over time, if I had no way to get real vintage HDDs I would be totally open to other storage media. What really …

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Re: New powersupply killed my motherboard

Posted on 2024-01-22, 21:45

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Definitely not an Antec. I have an actual PP-300V and it's packed full of components, the transformer is much larger and more appropriate for 300W. Quite heavy.

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Re: Floppy drive maintenance - Lubrication options

Posted on 2024-01-22, 21:39

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks for the replies guys! I guess I'll go with silicone grease then... even though both the rod and the screw are metal on metal there are plastic parts nearby, so I won't risk using the white lithium grease. I wasn't aware that it's aggressive to plastic. Still, it would be nice to find some …

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Floppy drive maintenance - Lubrication options

Posted on 2024-01-21, 22:45

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I recently got a Mitsumi 5.25'' floppy disk drive, it was very cheap and visual condition was good but it was listed as "not working". However, in the pictures I noticed that the fix would probably be very easy, as the solder joints on the small PCB with the power connector had clearly cracked. When …

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Re: What modern PSU can be used with high end Athlon XP retro build ?

Posted on 2024-01-20, 19:30

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Not trying to thread necro, but what series of caps did you use to recap the enermax with PCE-TUR? I recapped a 465-VE and 301-VE with Rubycon ZLJ and they must be too low ESR as my oscilloscope has them oscillating on the output unfortunately. Also you are totally correct on these crappy caps …

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Re: Anyone with knowledge about customized AT PSU?

Posted on 2024-01-20, 19:13

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I have one of those (or one very similar at least), it's basically an ATX power supply without the 3.3V components fittedand AT-style connectors instead of 20-pin ATX. The soft-off works exactly as in ATX, with the purple wire being +5VSB and green is PS_ON. By looking at the last picture, both the …

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Re: Voodoo2 SLI cooling

Posted on 2024-01-15, 21:10

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by TheMobRules

in Marvin \ Video

in Marvin \ Video

Nice! I had one of those printed by PCBWay a while back, but I put it into storage for a few months and when I took it out for testing it had bent and broke when trying to straighten it back. Probably due to the material they used to print it... What type of filament/material did you use?

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Re: 486 motherboard. Raising from the dead.

Posted on 2024-01-12, 03:30

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

By the way, that UMC chip is a clone of the CHIPS 82C206, which was commonly used as an integrated IRQ/DMA controller + RTC on many 286, 386 and 486 boards. This datasheet can help you troubleshoot problems with the CMOS settings and other stuff, and has diagrams for the battery backup circuit: …

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Re: 486 motherboard. Raising from the dead.

Posted on 2024-01-12, 03:18

by

by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Remind me: where are the bios settings stored?? The UMC UM82C206L chip has a small amount of memory and can switch between PSU and battery power when you turn off the system, so that's where the CMOS settings are stored. That chip also provides a real-time clock (there's probably a 32.768KHz chip …

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Re: Slot 1 CPU fan 3 pin cable

Posted on 2024-01-11, 03:30

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Looks identical to the stock cooler used by Intel on the boxed processors. For reference, this is my P3-800 where you can clearly see the connector that plugs into the fan: Filename P3_800.jpg File size 310.33 KiB Views 291 views File comment Pentium III 800

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Re: Slot 1 CPU fan 3 pin cable

Posted on 2024-01-10, 23:20

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by TheMobRules

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Not exactly sure what model of cooler you have, but I think this is the cable that comes with stock Slot 1 CPUs. Maybe it's the one you need: https://www.ebay.com/itm/184606983403

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Re: Significance of the M markings on 90s Roland music boards?

Posted on 2024-01-10, 20:51

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by TheMobRules

in Marvin \ Sound

in Marvin \ Sound

Not sure what they mean, but on the first picture the large M is actually the Matsushita (Panasonic) logo, so maybe it's something related to that? Maybe they made the PCBs and use that code as kind of a revision number as you suggest...

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Re: 2024 - End of the era of Retro Computing Youtube channels?

Posted on 2024-01-09, 16:56

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by TheMobRules

in Milliways

in Milliways

The C64 repair thing is something that has actually reached an unbearable level of saturation to me, not talking about any channel in particular. I can die happy if I never see another C64 repair video again, especially when 99% of the time it's one (or more) of those stupid MOS chips that decided …

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