Hi welcome to Tear down Tuesday Yes, Retro Computer time again. I Love Retro Computers. This one is from my Personal Collection it's the IBM PS2 model l40sx Oh, look at this baby! Uh, around. it's not hugely old in the scheme of retro computers.

It's um, early '90s vintage about 1991 I think is a release date I uh bought this back in about 90, 92, 93 or something. They were clearing them out. Uh, absolutely. Dirt Cheap I Couldn't resist getting it and it is a beautiful machine.

IBM's PS2 line of course was designed to counter all of the Clones coming out and absolutely killing them in the market around about that time, so they designed to. They changed the architecture to micro Channel and did lots of proprietary uh stuff and came out with the PS2 line. A lot of people don't know that they actually made a couple of PS2 laptops and this is one of the first ones of them. The L40, SX and uh I have the original power adapter I have the well not the original reference diset but I've got a reference diset.

uh, the original manual and I did have the original case on it, but I got this out of my roof space at home and no, the case was pretty much starting to rot away. so I ditched that but it's still in very good condition. So let's take this puppy apart and see what's into it. But I'm going to violate my rule and actually turn it on first cuz I know everyone wants to see this sucker working so hopefully it still works.

Now it is your classic clamshell design, but very, very thick unit I mean it's you know, not exactly slim at all. Yes, that is a 1.4 Meg uh, 3 and 1/2 in floppy in the thing. it's fairly light. you know it's not massively heavy.

It smid in under three kilos on the back. Here we have ourselves a yes parallel printer port Rs232 serial uh, that's for the external numeric keypad which I have which I forgot to uh, show you I've got that here somewhere. that is the battery. the battery is missing I think I've long thrown that out and uh, a dock expansion connector external VGA connector and that's about it.

Ah yes, there it is. external numeric keypad. Ah beautiful. But the thing I absolutely loved most about this machine was the keyboard.

In my opinion, the best feeling keyboard ever Made it and it was, actually, uh, quite well regarded. This uh, notebooking to for uh, journalists and writers and things like that because I I can't convey the feel. You know it's got that tactile feedback, but sort of a little little bit spongy. It's just absolutely perfect.

I can't convey the quality in the keyboard and it's just phenomenal. and I've never touched a keyboard like it since. Just oh beautiful. And there's the money shot.

Oh look at that. I Seriously, words cannot convey how beautiful this keyboard feels. Oh, check out the size of this power adapter though. It's absolutely enormous.

fairly lightweight. It is actually uh, switch mode. it's a 15 volt uh 2.7 amp Universal voltage one made in Japan by the way. Fantastic.

but uh yeah, this was really big, thick and clunky to carry around. it was Thicker Than The Notebook itself and when you tried it, didn't the carry case didn't have like a separate pouch for this thing so it's not like you could easily carry around the AC adapter. That was a real mongr of a a bad point about this uh particular machine. Now there's one thing I did really like about this machine is these LCD enunciators here all the ones all along here.

As you'll see, hopefully when we power it up it seems to be working here I've actually plugged in the the power at the back and we got in our get in our battery light even though there's no battery uh charging there and well I just loved the LCD As far as the engineering point of view went, they weren't pissing away current with driving LEDs which almost all other Uh notebooks had back then they went to the trouble to do this big LCD strip across there I can't obviously I think it's just one big strip right along the um top there, but we'll see that when we take it apart. but I thought that was a nice touch. and as I this thing isn't too retro in terms of uh IBM like a you know regular Pc architecture, it does have an Intel 80386 SX processor running at 20 MHz which you know for the day wasn't all that bad and it had a whopping 18 Meg of Ram uh yes you can only use the regular 16 Meg but the extra 2 Meg you could use as EMS memory on this thing and uh floppy drive. it had like a I think a 20 or a 40 m hard drive in the thing I'm not sure if that will still work or even if there's one in there we'll find out.

and the screen monochrome only. um, that was a you know Fair disadvantage I think most a lot of notebooks had transitioned over to pretty crappy color screens back then at least so were color. I think it's only VGA res like 640 by 480 and if I remember rightly the contrast on it was pretty small and the view angle and that sort of so not the world's best screen but with that beautiful keyboard on it and you know 8386 SX processor run at 20 megz it was okay. Had an auto manual switch over here and that was for the uh power saving mode and you could just switch it over to manual mode which I had it set up to for like you know, maximum processor uh speed so that was like super duper fast mode if I wanted it to crunch numbers or I'd whack it on to uh automatic mode where it'll go into Auto uh power saving mode and it was quite uh, you know, quite decent.

uh battery life on the thing if I remember correctly, nikad battery so you got to remember it for its day 1991. So all right here we go. Let's boot this puppy up and see what we get. Yeah, all the annunciators are lit up, can hear the hard drive spinning, it's seeking the floppy drive, and oh yes, we have something on the screen.

There we go. there, we go look at that it only had. oh it's only got two Meg only got two Mega Memory There we go, that's not much at all. Press F1 to continue.

No, hello there we go. Woohoo it works. A hard drive obviously didn't work or is not uh uh, formatted or something. but uh, we are in to Basic.

Check it out. Copyright: IBM Corp 1981 It still has Basic in ROM Beautiful. A look at that. Here we go: 10 print Hello wh World 20 Go to 10 run Tada Basic in ROM Classic.

All right. I'm going to try that again, but I'm going to try the uh reference disc I No sort of nothing growing, no fungus growing on the disc or anything like that. Let's uh, see, hey there we go. All the annunciators had an over temperature uh warning on there there we go.

Memories booting up only had 2 Meg but that was enough. Back in the day it was. it did support 18. Meg As I said I have no idea what 161 is or 163 Have no idea.

Yep, it's loading. It's trying to seek the floppy and uh oh I didn't hear it seek again? No, it tried once. Oh there there it goes. again.

a it's fighting. Will it boot? Come on, you can do it. Yep. Yep.

seeking. I Think there's a good chance this will work? I I Don't hear that sort of seeking failure. You know kind of that sounds like hey, there we go IBM PS2 System 2 Model l40 FX SX Reference disc at 1.0 There we go. Copyright: 9 91 The floppy Dry still works.

The disc still works. This is my backup copy of the reference disc. I'm not sure where the original reference disc went, but uh, this puppy is working. Backup battery error.

Oh okay. there you go. That's what 161 is. Okay, the backup battery in it.

Maybe it. it could have leaked on the motherboard or something or it's definitely dead. Um F8 to go forward. Okay and uh.

once a yeah blah authorized dealer blah blah blah and message. If you want to make a backup copy, do it now. blah blah blah blah blah. enter the date and time time before running I Don't care, just go I Want to see the Doss prompt I think it was um well actually no I thought I was going to say it was uh no, it wasn't It wouldn't be Ms Doss it would be uh Microsoft it would be um IBM of course.

whatever. 1990 Automatic Configuration: I Know everyone wants to see inside this thing but sorry I'm having too much fun booting this thing up so you're going to have to bear with me. Automatic Configuration: Not sure what it's configuring I thought it I thought it just booted into dok and this and this has various utilities on it to test it and things like that. if I remember correctly.

um so no, no, it's rebooting. Okay so what? It configures the Seos. Ah, the old floppy seeking noise. Back up there We go.

There we go. It's a configuration. youtil back up the reference This set configuration set features password test the computer display revision levels set features What have we got here? It's got to read the dis just to go to another menu. What couldn't they couldn't compile everything into the one XY and uh, do it that way.

Set features menu install set feature What bloody hell. Keyboard: no speaker oh whoopy dooo forward autom make typ R LCD Color versed H We could test the computer but you know, doesn't matter. It works and there we go. Bias Version: Uh 27 for the second 91.

All right. well let's take this puppy apart. Everyone wants to see what's inside it and uh, if I remember rightly the Uh, keyboard just pops right off and uh, you can actually see some of the motherboard that way. Uh, not all of it though.

So lift it up and I think that's it I think this yeah keyboard pops out. We might have a surprise in here. Yes we do. We do have a surprise.

it's still in there I was hoping it was. Let's check it out. And yes, this puppy is souped up to the hilt. Here's our Intel 80386 SX uh 20 MHz processor down here.

They got that in a fine picture. quite a flat pack, but I populated it with the um it with the I sorry, uh, 3C 87 SX 20 MHz Math Coprocessor. Look at that. So this was an absolute screamer as far as uh doing floating Point calculations all done in Hardware in the math Cod process.

So people take that for granted these days that the processor just work. but back then, your regular Intel processor was dog slow at any uh floating Point stuff unless you actually added the math Cod processor in. Now it's all just builing. Nobody ever thinks about it anymore, but uh, back then that was a real big deal to go out and buy this and this was H this IIT one I Can't remember the exact specs, but it was like, you know I don't know.

at least a couple of times quicker. uh, more efficient than the genuine Intel 80387 uh Math coprocessor. So this was the the one to get back in the day and wonder what happened to IIT goodness I think that was probably their only product was this math Co-processor made in the USA just like Bruce Springsteen And there it is. the keyboard made in the United States of America USA USA USA Everyone loves it when I see say that I Get it so wrong Now a good lot of your circuitry is accessible in this thing without having to go any further.

We got our two memory expansion slots here I think I did have them populated at one stage but I probably uh took them out so I don't exactly recall. We got a huge custom gate array over here. it's got its own uh revision number. We got our little got our ROM there uh socketed as I said main 386 SX processor the um optional uh usually didn't come populated 386 co-processor and uh the WDC System Controller will take a look at and whole Bunch uh well we've got some uh got the internal 2 Meg of uh memory here and a whole bunch of 74 series logic.

Everywhere else, there is quite a significant amount of 74 series logic 74 acts, uh, 373s, 2 44s. There's Uh 125s and all sorts of 74 HC uh series logic. Uh, looks like we have a small surface mount regulator down there and pretty much um, all of its surface mount. IBM Of course optimized this thing for uh manufacturer.

Tiny little speaker and this flat Flix ribbon would be going off to the Uh as I said the LCD strip up there and this WD 76 C10 huge big Uh package in here. the biggest package by far and uh, it is the main System Controller it. It handles, uh, memory interfacing of course. that's why the memory's coupled right into it up there and uh, you know, timing in all sorts of the bus interface stuff for the Uh SX processor right next to it here.

Curiously, it's got Proto on there and well, I don't know what is that it? Surely it's not a prototype chip and anyway, we' got ourselves a date code 9th week uh, 91. So this one. it looks. Most of the chips around here look to be about that sort of vintage so it looks like it was manufactured in 91.

This one, but prototype E I Doubt it. this is production machine so don't know what Proto means and look at that classic. The old 8042 PS2 Keyboard controller. ah brings back memories and it looks like they got some sort of uh programmable device there.

probably like a little uh gal or Pal or something like that. I'll just whip that label off and we'll have a squee there. shall we? Got to have a look? So yeah, it'll be like a you know, just a little H hard to read. Let me get in there and N85 c224, H Intel and yep sure enough that is an Intel 8 macro cell plld so tiny little bit of glue logic there and we can lift Out ta.

oh no the floppy. oh yep, there we go. We can lift out our top cover there and we got ourselves there is our ah ah, the hard drive. Okay, that's interesting.

Now it's coming back to me now it's coming back. All right, let's have a look. We've got ourselves a uh power supply up here and there's our there's our backup bat actually has two backup batteries so this is rather interesting and my pommy viewers will love this. Look at this hard drive.

This is not the oral original but check it out. made in the UK There you go the Old Dart Fantastic! that was back when IBM made hard drives before they uh sold it off. Five works from 5 Vols made in the UK oh it's just beautiful. Anyway, this was the reason it's not original is cuz it has a dwoo sticker on it.

remember dewoo the cars didn't they go busted or something? Well they made notebooks as well and I had uh a dat wood notebook which I used for many many years. It was like a real Ultra compact uh notebook. It was fantastic. So obviously at some point I took the hard drive out of that and uh put it back up.

put it back in this thing. So um, the day wo one was after this? so I believe? Yeah, Well, Feb 96 there it is. Um, so yeah? I obviously I tried to boot this thing up uh, back in the uh, probably the late '90s with that uh old Dewoo hard drive I can't remember I think I tossed it I think it was. it just went bung.

Anyway, dewoo oh, there's a blast from the past, so there's no reason why we couldn't really replace this with a solid state equivalent. uh, hard drive. These days, you wouldn't replace it with a with an actual uh hard drive I don't think you probably you know, put in some sort of solar State equivalent. You could get this thing booted up fairly nicely I think and then it would be silent of course.

cuzz there's no fan in this sucker, so it'll be completely silent apart from the beeps which could, uh, turn off and uh, yeah, it' be an okay machine for some purpose like that. Now underneath the keyboard here. we got a couple of interesting things. Um, first of all, this is our heat sink here.

and look, it's not your traditional, um, anodized aluminium. so um, that's rather interesting. It's a that's a 7805. There's a, looks like there's a diode.

there. got a little ferite bead on the lead there, just taking a bit of edge off. the uh, a bit of edge off the edge so to speak, pun intended. So we got ourselves an LT 1270 switching regulator there.

So of course, this is all a switching uh switching converter all around here. All these low ESR caps. they put a nice cut out in the PCB for those to lay those down flat. so that's rather interesting.

And they've laid all the other ones down flat. of course. no room vertically. it's got to fit under the uh floppy drive.

and uh, that's about a she Road A couple of there we go. There's that little uh, Ferite bead there I Like that bit of significant interest. Take a look over here. look at this vertical Riser Hybrid I Can't see what's on the other side much.

There's a oh yes, I Can there we go? I can just take out the Tada Too easy. Um, yeah. we've got an S So8 on the back back. there two S So8 actually and a couple of other things and a couple of, uh, thick film resistor networks.

Let's take a look at the other side. Well, that's interesting. Look at that. a 4066 phase lock loop and 7404 there mounted on that uh, ceramic Riser board.

Why? why they've gone to the effort to do that hybrid is beyond me. Is it that critical that their Phas lock looping? You know that they uh generating in some clock via a PLL for I Don't know what. But yeah, very strange. And then the other interesting thing is the flat Flex ribbon cable.

They've gone to the effort to put the parallel port up there, not surprising, really. squeeze it just behind the heat sink in there, keep it very low profile and uh, they've put some little Ferite beads on there once again just for uh, you take the edge off things and uh for uh Emi compliance. And that tucked away on the back of the heat sink there looks for all the world like a thermal cutout switch. Just one of those you know, cheap ass, uh, simple, uh ones that you get for uh, any sort of, you know industrial application for a rough thermal cutout for over temperature.

you know if that heat sink hits 80 or something Bingo it just disconnects. probably the uh input, uh, the straight. You know it just disconnects the uh input or the battery input. We got ourselves a linear Tech LT 1137 there.

that's for the RS 232 driver and most of the other stuff around here is uh uh, switch mode power supply. We got an unpopulated device here that looks like a crystal which goes next to it. uh, little four pin metal can Crystal So I don't know what would be going on there, but we have ourselves a lattice gal 20 V8 down in there as well. So once again doing some some glue logic and that WDC controller once again got Proto and Proto over here.

So yeah, got it, Know must mean something else. Uh WD 76 c21 that's the combined uh, floppy Drive controller and real time clock and that WDC 76 C30 there. that's like a uh, well, 3 in one. Basically, it's a peripheral controller so it does dual serial, pull control, parallel and all that sort of stuff.

and it does interrupt moldy fxing and also clock generation as well. So fairly versatile little device. We've got ourselves two batteries in this thing. As I mentioned before, this one's a rechargeable Nikad battery 45 milliamp hours.

so I'm not sure what the hell that thing's uh doing in there and the other one is, uh, a lithium primary battery. That's the one that's uh, most likely flat so it's lost all its uh, content, all the Seos contents and you're probably thinking, well, where is the video? uh card, Where is the video display chip? Well, here it is. WDC Again, they made a whole slew chipsets to design for everything. A complete PC architecture AC system.

This is a WDC you guessed at uh 90 C20 there's a 90 C10 in here, 90 C20 and the 90 C30 uh and the 90 C21 that we have in this thing. So they've got the full WDC chipset support. Anyway, this is, uh, the graphics uh, controller supports monochrome and external uh VGA interface 640x 480 VGA We've got ourselves the display memory here, not sure exactly how much, and uh, there's like a it's like a 30 MHz L 28 MHz LCD clock or something like that. Not very, uh, quick at all.

not very powerful. 32 uh Gray Shades uh for the mono LCD it supports up to 256 color or something like that on the external color CRT interface. but yeah, nothing fancy. just VGA interface.

All you gaming nerds must be gone. What the hell was that thing? Where's the fan on it? Where's the water coin can I play crisis on it and over in this corner. We got the LCD cables just going off there, just through the rotating hinge there. uh, we've got ourselves a Ferite of course just to take the edge off things again.

And that little cable going down in the back there? there must be some sort of micro switch in the lid that's for the that's to detect that the lids shut so that it can shut the thing down. and I tried to get the screen open. There were two security torx bits in there and I managed to get those out. but uh yeah, it's not coming apart easy.

I Really don't want to uh uh, damage this thing I Want to keep it in one uh piece? There's not. You know. there's probably a trick to actually get in the front cover off the screen, but I yeah, I tried and uh well. there's not much of Interest behind there Anyway, it's just going to be a, you know, a daggy old 640x 480 mono LCD So nothing hugely fancy, so please forgive me for not going into there.

So there you go. That's a look inside an early '90s vintage in particular 1991 vintage IBM PS2 Not many people knew there's a PS2 laptop, but there was PS2 model l40 SX and as I said beautiful keyboard and it's quite nice engineering inside this thing. I mean in terms of uh, thermal, you know the thermal staff thermal out the protection. the Emi stuff.

They've done everything really well. They got that nice little hybrid in there doing something and made in the USA it's just. it really is a nice machine and uh, you know it's hard to fault this thing. I'm not sure not absolutely 100% how competitive this was when it came out in 91.

Probably not hugely, uh, competitive, but probably wasn't uh, too far behind the curve cuz as I said, you whack the Cod Co processor in that thing which would have low power shutdown modes. That's the other thing. The IIT math co-processor in here I believe was lower power. Try and find a a data sheet or a, you know, a brochure for this thing back in the day if I can, but you know 20 MHz um, 386 SX processor in the thing.

It wasn't too bad at all and he could probably use it as a reasonable little uh, you know, modern machine just for doing some uh task running Doss off a off a solid state drive or something like that. So really high quality and that keyboard was just superb quality. Really? I Can't tell you how wonderful this feel is, but if you ever get a chance, it's just fantastic. I Know it's personal preference, but I think this thing was highly regarded back in its day for uh, the feel of the keyboard.

A lot of people used it for a long time just because of that. and well, there you go. It's a really nice little machine. I like it early night it's it's not too red show.

it's not, you know 1980s or 70s ret show but classic early 90s stuff and made in the United States of America Got to love it and as always I'll link in all the data sheets to all the uh chips on this thing down below. so check them out and if you want to discuss it, jump on over to the EV blog Forum that's linked below down as well. And also don't forget to subscribe to my Eev blog 2 channel. the second Channel where I put uh, just a random uh material and stuff that doesn't go on the main blog but it's still semi- related.

so um, there you go. Catch you next time.