PeterLI wrote:

That is not true. Many things are worth saving. I am just stating that reality is different: not everything is saved nor do many things actually sell. Not even for free. I am giving away a PS/1 for shipping and nobody wants it so far. Perfect example and not the first example.

Free PS1? Oh god... now I wish I lived in the US.

not everything is saved

Right. Most people don't see the use in old stuff and don't bother keeping it.
That is exactly why small groups like these should try to preserve as much as we can

Good luck! I do not have the funds or space to hold on to everythting. 🤣

Are they eating into your market share Peter? 😉

I threw away a PS/1 486 a few months ago. Pulled the cpu, cache and anything else I deemed useful off it though.

Apologies for the late reply. Also, apologies to PeterLI because, if I had the slightest idea of what I would do with a PS/1, I'd be all over that. As is, I've only become aware of their existence through your mention of the one you're trying to give away. 🤣

So, here are the pictures of the power supply with the attendant measurements (I intended to have the ruler in the pics for scale but my phone camera is rubbish, so there we are...).

Now, if anyone can point me to a good tutorial for re-capping a power supply or even diagnosing the circuit, that might be a shorter line to getting this thing in order, but my circuit board soldering skills have not been tested beyond soldering an iPod Nano battery to the main board, so that may be slightly more advanced than I ought to go. Worth pointing out, I did remove the cover of the PS and couldn't find any leaking or bulging caps, so whatever went wrong internally, it's not giving me any visual cues.

Probably a good time to suggest that if anyone can point me to a good resource for using a multimeter to diagnose the circuit, it'd probably give me more info to work with... 🤣

Yeah, I'll go put on my "n00b" hat about now. 😒

Sorry to keep spamming my own thread, but I encountered something elsewhere on a thread regarding IBM 5150 power supplies.

Is it possible to just take the guts from another power supply and transplant them into the chassis of the original Laser PS? I'd have to reconnect the board to the Laser PS chassis' AC plug and integrated power switch and ground, but I can't imagine that's some beastly task.

What are my odds for not singeing off my eyebrows or bricking the mobo?

Technically it shouldn't be hard, as long as the board fits the casing. It appears to be pretty standard AT for me, with the switch fixed to the PSU itself instead of being in the front of the case.

I'd take the innards of an AT PSU, de-solder the original switch and put the new one in place and be done with it. If the only spare PSUs you have are ATX it can be a bit more involved. If it has a -5V line you can de-solder the ATX MoBo cable (leaving the green cable and a black one), solder the AT power cables from the old PSU (being careful to not mess up the voltages) and solder the green and black cables to the switch (or short them if the ATX PSU already has a switch and you replace it with the one in the old case).

Fortunately, I was given a spare AT power supply, with the only issue being that it was a standard "external power switch" unit and would have required case surgery to be mounted. This offers some promise.

I'll give it a whirl tonight and report back with the results. Thanks very much for the info.

And we have life! It purred to life with the transplant guts in the original PSU chassis.

As it happened, the soldering iron wasn't even necessary as both boards used a three pin header to connect to the AC outlets and switches. The color coding of the wiring was different, but there were no polarity issues or anything of the like and my eyebrows (and 486) are intact and happy.

The fan did need to be transplanted from the old PSU chassis because the Laser fan used a smaller header than the transplant unit. But, again, plug and play.

So, the box now has power. The final challenges involve:

a.) Figuring out how to mount a hard drive and 5 1/4" floppy drive in a chassis that requires rails when I have none of said rails;
b.) Figuring out how to get the ISA drive controller to recognize a hard drive; and
c.) Securing a new CMOS battery socket and attaching it to the mobo so I don't have to set the CMOS every time I fire this animal up.

If anyone has any suggestions on A and C, I'd appreciate it. I vaguely recall happening on instructions somewhere on here for converting a button battery socket to work with these old motherboards and if someone could link me, that'd be a huge help as I'd prefer that to a 4 AA battery unit - which is all I've been able to find on eBay thus far. I'm still digging into the forums for info on getting larger drives to register and I have a lot of info to work with, so I should be set there. I just need to figure out how to affix the thing when all is said and done. Worst case scenario, I may go compact flash on this so it's one less thing to worry about.

Does the motherboard have an external battery connection?

If it does, that is the safest option with an external battery (pack) away from the motherboard

Great job on the PSU rework

I can't take too much credit. I think this task was about as easy as a beginner could have hoped for. It was gratifying to see it work though when all was said and done.

The original battery WAS an external box containing 3 AA batteries that had exploded and corroded all over the front of the chassis - fortunately on the exterior as it was mounted under the plastic front bezel but in front of the metal. It did leak all over the indicator board mounted to the front, but only seemed to have taken out the reset switch, which seems to be 100% non-functional. There are way worse things.

With an external box, all I've found were 4 AA battery setups and the original mount for the battery doesn't have enough extra room for that kind of thing. Is it possible to jury rig a button battery to work with a 486 motherboard or is the voltage wrong for that? If nothing else, I could just pick up the battery setup I've found online and double-sided tape the thing to the back of the chassis to keep it out of the way. It just seems a tremendous waste of space.

Runicen wrote:

I can't take too much credit. I think this task was about as easy as a beginner could have hoped for. It was gratifying to see it work though when all was said and done.

The original battery WAS an external box containing 3 AA batteries that had exploded and corroded all over the front of the chassis - fortunately on the exterior as it was mounted under the plastic front bezel but in front of the metal. It did leak all over the indicator board mounted to the front, but only seemed to have taken out the reset switch, which seems to be 100% non-functional. There are way worse things.

With an external box, all I've found were 4 AA battery setups and the original mount for the battery doesn't have enough extra room for that kind of thing. Is it possible to jury rig a button battery to work with a 486 motherboard or is the voltage wrong for that? If nothing else, I could just pick up the battery setup I've found online and double-sided tape the thing to the back of the chassis to keep it out of the way. It just seems a tremendous waste of space.

Unless the board originally used 3V, a coin cell would probably be too low of voltage.

Am I likely to have a problem with 4 AA batteries in the new enclosure when compared to the 3 battery original, or is an excess of voltage a non-issue?

If I'm remembering how this stuff is tallied correctly, at 1.5 volts each, 3 AA batteries would be 4.5 volts in total for the purpose of the motherboard and 4 would be 6, right?

Runicen wrote:

Am I likely to have a problem with 4 AA batteries in the new enclosure when compared to the 3 battery original, or is an excess of voltage a non-issue?

If I'm remembering how this stuff is tallied correctly, at 1.5 volts each, 3 AA batteries would be 4.5 volts in total for the purpose of the motherboard and 4 would be 6, right?

Correct. Quite a few people use 6v although I personally stick with 4.5 even though 3 battery holders are less common

So, having moved recently, space is at a premium and I find myself (again) trying to figure out what to do with this 486.

As things stand, I've gotten the power supply issue worked out, but now I'm having trouble with the IDE controller card installed in it (getting to BIOS, but unable to boot from any hard drive I plug into it). However, even if I manage to get that done, the case itself has oversized drive bays which require rails in order to mount even 5.25" drives, let alone standard hard drives.

All that said, what I'm starting to wonder is, if I do decide I absolutely want to make this thing work, what are my odds for being able to find viable replacement rails (i.e. are those Dell rails that are abundant on eBay or something along those lines usable?) to use this chassis? Failing that, how proprietary were 486 motherboards and would it be more worthwhile to pick up a "new" AT case that doesn't have that quirk for assembling components?

Or, short version, if you had a setup like this one and wanted to make it work, how would you get it up and running while spending the minimum possible?

Does the machine boot from floppy? Do you know if the machine supports drives bigger than 500MB? I know in the past I've just repartitioned/formatted 2GB drives as 500MB so that they would work on my 386-DX 40 - rather than mess around with any kind of overlay software.

Runicen wrote:

All that said, what I'm starting to wonder is, if I do decide I absolutely want to make this thing work, what are my odds for being able to find viable replacement rails (i.e. are those Dell rails that are abundant on eBay or something along those lines usable?) to use this chassis? Failing that, how proprietary were 486 motherboards and would it be more worthwhile to pick up a "new" AT case that doesn't have that quirk for assembling components?

If you have at least a pair, you can just draw them in something like SolidWorks and get them 3D-printed.

The shop i worked for used to sell laser pc's. I have nice memories of them. Those rails where nice back in the day. Made it so much easier to install drives. We used to have a pile of them. Maybe my old collegue may have some of those brackets.
Last week i visited him and got a laser branded mechanical keyboard from him.
You could drill some holes in the bottom of the case and mount the harddisk that way. Using the bottom screwholes to secure it.
To bad shipping from and to the us is so expensive.

You're lucky, it looks like a standard 486 motherboard. Laser also made a PC clone that looked like their Apple IIc clone only with blue highlights on the case instead of red and it had no slots at all. You were stuck with whatever options they could squeeze onto the motherboard. Those are the first ones I think of whenever someone starts talking about Laser computers.

seob wrote:

The shop i worked for used to sell laser pc's. I have nice memories of them. Those rails where nice back in the day. Made it so […]
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The shop i worked for used to sell laser pc's. I have nice memories of them. Those rails where nice back in the day. Made it so much easier to install drives. We used to have a pile of them. Maybe my old collegue may have some of those brackets.
Last week i visited him and got a laser branded mechanical keyboard from him.
You could drill some holes in the bottom of the case and mount the harddisk that way. Using the bottom screwholes to secure it.
To bad shipping from and to the us is so expensive.

You have me wishing that teleportation technology was a reality! 🤣

If it's going to come down to modifying the case, I'm half tempted just to transplant the motherboard to a standard AT case instead (easier to match power supplies as well if this one goes).