schmatzler wrote on 2020-10-25, 15:27:

dr_st wrote on 2020-10-25, 13:08:

My A21m recently died. Not due to GPU failure, but the more common blink-of-death (failure of the power control chip). Maybe that is also heat-related.

I recently fixed one! All it needed was a new ADP3421 chip, I've got 20 of those on Aliexpress for a good price. 😀

I tried this workaround, which didn't work. Replacing the ADP3421 is the logical next step, but I am not sure I'll ever muster the energy to deal with it, especially since, as you said:

schmatzler wrote on 2020-10-25, 15:27:

The machine is pretty useless, though. It even struggles running Half-Life in VGA mode.

I really only used it for a DOS/W98 games testbench, but I don't seem to find much motivation for this kind of activity at the moment.

I have a A21p that occasionally shows BOD symptoms, but after resting for a month or two boots fine again. It's on it's way to death anyways. So I'm thinking of possible repair. What do you think about this fixing method with a 2 kOhm resistor (described here https://thinkwiki.de/BoD)? Is this a long term solution?
Does A21m have the same video chip as A21p? Mine runs HL1 fine, except for some artifacts with aliens blood on the walls that flicker a bit.

schmatzler wrote on 2020-10-25, 15:27:

I recently fixed one! All it needed was a new ADP3421 chip, I've got 20 of those on Aliexpress for a good price. 😀
The machine is pretty useless, though. It even struggles running Half-Life in VGA mode.

Bondi wrote on 2020-10-25, 15:45:

What do you think about this fixing method with a 2 kOhm resistor (described here https://thinkwiki.de/BoD)? Is this a long term solution?

Posted at the same time, I see. 😀 Well, it didn't work for me, as I said. 🙁

Bondi wrote on 2020-10-25, 15:45:

Does A21m have the same video chip as A21p? Mine runs HL1 fine, except for some artifacts with aliens blood on the walls that flicker a bit.

A21m has either ATI® Rage™ Mobility M / AGP 2X / 4MB or ATI Rage Mobility M1 / AGP 2X / 8MB. A21p has ATI® Rage™ Mobility 128 / AGP 2X / 16MB, so quite a bit better (at least for the time). It's the same in A22m vs A22p, except A22m can also have Mobility M3 (which is like M1).

The A22p can run Half-Life very well. I had one back in the day and used it for LAN parties.

I have an A22m with the slowest Rage chip of them all, though. Half-Life crashes in OpenGL mode (locks up the whole machine) and in D3D I can barely get it to work in VGA. So yeah, that machine is only useable for pure DOS games at best.

What do you think about this fixing method with a 2 kOhm resistor (described here https://thinkwiki.de/BoD)? Is this a long term solution?

I think, with those chips, there is no long-term solution at all. If the resistor method works, that's fine. If it doesn't, you need another chip. But all of these chips seem to have the same fault and will likely fail at some time in the future.

Interestingly, the chips I've got from AliExpress all seem to have date codes around the year 2000. Except one, that had one from 2006. That's the one currently running in my A22m.
Let's hope the manufacturer fixed the deteriotation problem in the later ones.

dr_st wrote on 2020-10-25, 15:50:

Posted at the same time, I see. 😀 Well, it didn't work for me, as I said. 🙁

Ah, right on time! 😀 So it did not work... Thank you for the info, I'll go for the entire chip replacement.

A21m has either ATI® Rage™ Mobility M / AGP 2X / 4MB or ATI Rage Mobility M1 / AGP 2X / 8MB. A21p has ATI® Rage™ Mobility 128 / AGP 2X / 16MB, so quite a bit better (at least for the time). It's the same in A22m vs A22p, except A22m can also have Mobility M3 (which is like M1).

Cool, I love my A21p, despite the fact that I avoid playing on it due to possible video chip failure 😁

Bondi wrote on 2020-10-25, 16:24:

Cool, I love my A21p, despite the fact that I avoid playing on it due to possible video chip failure 😁

I used to be afraid of that, but since I acquired a hotair station I feel like I can fix almost everything.
For the GPU I only need a stencil and the solder paste to recreate the balls under the chip. 😁

schmatzler wrote on 2020-10-25, 12:44:

The A22p had the Rage chip on the bottom of the case, with no airflow.

Presario 1800 also does that. But it has thermal pad which helps spreading heat to the case, although the case is plastic.

Maybe doing something like this would be a good idea? Mabe there is enough space to spread the heat over a copper sheet. I could try that with my laptop and I guess it could also work with A22p and the others. The efficiency wouldn't be great, but it could decrease peak temperatures.

Does Compaq Presario 1800 with ES1946S Solo-1E support General MIDI natively?

vorob wrote on 2020-10-25, 23:14:

Does Compaq Presario 1800 with ES1946S Solo-1E support General MIDI natively?

I just tried Doom and Sim City 2000 under Windows 98 DOS mode, with MPU401 GM option, but there was no music. Music works only with sound blaster or adlib mode. That sound card doesn't have built in wavetable samples. But as you can see the driver provides address of MPU401 port:

I don't know if it would work with external MIDI modules, I have no such hardware.

Looks like I'll soon have this beast. I think its too oldy even for this thread, but still wanted to inform you 😀

No idea if it's working.

schmatzler wrote on 2020-10-25, 16:27:

I used to be afraid of that, but since I acquired a hotair station I feel like I can fix almost everything.
For the GPU I only need a stencil and the solder paste to recreate the balls under the chip. 😁

This reminded me some russian cars, that require the owner to be a car mechanic. Otherwise you cannot use it.
Yet we're talking IBM here 😁
And yes, hopefully the later ADP3421 chips are fixed.

So I've sorta fixed hinge in my Toshiba 2805-401. In geniusmeme.jpg way...

Nice 😀 I wonder what to do with my second Presario 1800 hinges. They both just shattered while opening the laptop, because they got stuck (lid was stronger than the hinges, looks like the lid is made of magnesium or at least some composite material). Inside screen casing i found some white powder, maybe it was cyanoacrylate glue, or just signs of humidity.

I cannibalized spare hinges off Presario 1600 which I bought just for that purpose (screen is smaller and doesn't fit, but hinges are the same). Maybe I can 3D print the shattered part of hinge with some strong material, or find someone who can mill it on CNC... But that protuding axle is absolutely stuck, it can't be rotated even after a week-long WD40 bath. So even if I make the missing part, I will be able to open the lid, but there will be no supporting force for the screen.

Guys, i was checking different old laptops and found that some dude made a proper scaling patch for old Toshiba: Toshiba Satellite Pro 430CDT
I wonder if such thing exist for Savage S3?

vorob wrote on 2020-10-27, 19:47:

Guys, i was checking different old laptops and found that some dude made a proper scaling patch for old Toshiba: Toshiba Satellite Pro 430CDT
I wonder if such thing exist for Savage S3?

Oh, thanks for that 😀 works great with my Libretto 70CT. Works even with Windows games, like Jazz Jackrabbit 2 in 320x200 mode (instead of 320x240, which had worse performance, but no black bars).

schmatzler wrote on 2020-10-25, 16:16:

The A22p can run Half-Life very well. I had one back in the day and used it for LAN parties. […]
Show full quote

The A22p can run Half-Life very well. I had one back in the day and used it for LAN parties.

I have an A22m with the slowest Rage chip of them all, though. Half-Life crashes in OpenGL mode (locks up the whole machine) and in D3D I can barely get it to work in VGA. So yeah, that machine is only useable for pure DOS games at best.

What do you think about this fixing method with a 2 kOhm resistor (described here https://thinkwiki.de/BoD)? Is this a long term solution?

I think, with those chips, there is no long-term solution at all. If the resistor method works, that's fine. If it doesn't, you need another chip. But all of these chips seem to have the same fault and will likely fail at some time in the future.

Interestingly, the chips I've got from AliExpress all seem to have date codes around the year 2000. Except one, that had one from 2006. That's the one currently running in my A22m.
Let's hope the manufacturer fixed the deteriotation problem in the later ones.

Yeah, my T21s fell to the BoD issue, and frankly, the 2 kOhm resistor "fix" doesn't really fix the chip falling apart internally - it merely makes the threshold for signaling a good power state to be lower. There are also mentions that for some people the fix is to replace the Tantalums around the CPU along with the ADP3421, but I am not sure how effective that can be. I have yet to find an effective, pin-compatible drop-in replacement for the ADP3421, which would make the machines less susceptible down the line. The chip is out of production so whatever stock is out there is likely just as old as the machine itself.

Getting an AMS laptop of some variant (cannot determine the model number, let alone the screen type and color, sound card, and other items). Pics soon once I receive the laptop (have it on vacation mode at the moment for the laptop).

Here's a video about the laptop: https://youtu.be/L7SPiA3uzBQ

Had to dismantle the system to replace the dead CMOS battery and will be put back together in the afternoon.

Pros:
LIF socket for upgrading the CPU (3.3V only)
ESS AudioDrive ES688
Coin Cell Lithium battery (soldered on the board and will be an accessible one by feeding the wires to the area where the Ni-MH used to be at for easy replacement)
Expansion port for installing a SCSI CD-ROM drive or variant, which is nice in of itself

Cons:
DSTN display that will be swapped with a TFT Active (will need to find one that'll fit in the chassis and the wiring meeting the requirements)

Scale of 1 to 10 for the range (1 being low range and 10 being high range): 7.5 since the DSTN is the big factor there, but the CPU upgrade is a cinch (not taking chances of installing a 5x86-P75 3.3V CPU).

Just going to leave this here: I had the same idea, but then I realized that no such thing exists. Some machines lack sound, most lack it in DOS. Others have worse than average LCDs. Only a few support a joystick. Some have an abominable pointer. Some take weird RAM that will be hard to track down. Some have tofu hinges. Some have exteriors that turn all tacky with age. Many have almost no parts availability, documentation, or available community knowledge. Some you'll never find drivers for. Some use hard to rebuild lithium batteries. Others have early SMD capacitors that have likely leaked enough to have damaged traces on the motherboard.

You just have to decide upon priorities. My first and foremost would be serviceability and popularity. It will break. If it works, it's just on borrowed time. And you don't need to be breaking unobtainium ribbon cables in the process, cursing as you pry here and there blindly trying to open up an undocumented machine that once you get it open reveals an acid-scarred board. I came to this conclusion after buying a hotshot first generation Panasonic Toughbook. And a Tidalwave clone palmtop... which had Thinkpad sticky case syndrome.

So I settled on a Tandy 1400LT. Because it's stupidly common, has a service manual, and is pretty much all early 80s through hole technology. Reliable like a cockroach, really. A 14 LB cockroach. I recognize a 7.16MHZ v20 and squashed CGA mono graphics aren't everyone's choice, so I think it's worth mentioning that Compaq Conturas seem unusually likely to show up working. You can at least get those with active matrix panels, and they seem to be aging far better than the more expensive Compaq LTEs and T4xxx series people actually wanted back in the day.

radiounix wrote on 2020-12-01, 19:23:

Many have almost no parts availability, documentation, or available community knowledge.

I had positive experience with Dell Inspiron 8100, although it's almost a "modern" laptop, but still compatible with Win 98 and DOS to some extent. Most of the parts are interchangable with i8000, i8100, Precision M40, M50, Latitude C800, C810, C840 series, even if there is different CPU socket, you can still use the GPU, screen, keyboard, case etc. Original Windows installation disks are easily available and and replacement batteries are also still produced.

radiounix wrote on 2020-12-01, 19:23:

So I settled on a Tandy 1400LT. Because it's stupidly common

Availability can also heavily depend on region, i have never seen it in my country, it's probably not so common outside America 😀

I have Toshiba T3200SXC which has similar form factor, I have never seen anyone else using it in my country, but it's so big that you literally could try to fit a baby AT motherboard or SBC inside if it ever fails. I already had to replace a screen and PSU, and I managed to use more modern parts (internal PSU now takes 1/4 of space it originally took, LCD is the same size but 10x thinner), it was easy to fit them because service manual has all necessary pinouts.