 This is my trusty Toshiba T1000. It's a XT class laptop and it stopped working. So I'm going to take it apart and see if I can figure out what's wrong. Do a quick inspection. I don't see any fluffiness. Now that's interesting. That explains why it's not working. Hey, look what I found in a junk drawer. Does this connector look familiar? This is probably the stupidest video I've ever done. And... DOS. One working computer, one elderly and slightly suspect battery pack. Well, I appear to have spoken a little bit too soon. This is wrong. So this is my Toshiba T1000 laptop with the lid off. If you saw my previous video, you know that I tried to replace the battery, which was kind of defunct with a bench power supply. And while that worked fine, the machine turned out to have failed. And I don't think it was my fault. So the most plausible explanation for this is that the capacitors have died. Which happens with old computers. These electrolytic capacitors have water-based electrolyte in them, which evaporates over time. And given that the machine generally smelled a bit funny when running anyway, it seems very plausible that they've just finally given up the ghost. And I should replace them. So that is what I'm going to be trying to do today. It doesn't have very many capacitors. It's just this little cluster around the power supply and a couple of decoupling capacitors under the floppy disk drive. So even with my mediocre soldering skills, that ought to be possible. So let's try it out. First step is to remove the motherboard. Okay, here we are. And this is actually a little bit different from the other board I've got. Well, the other two boards I've got. In that this cap here is present. However, on the others, it's unpopulated. And I notice that there's a bit of grimness around here that's not so hot. It doesn't look like the cap is leaking. But here we have the little decoupling capacitors. Honestly, these are probably fine. It's these big chunky electrolytics that are problematic. Oh, and there's a tantalum capacitor here. These have a bit of a tendency to explode, but I think that one's fine. I don't see any obvious leakage, but caps don't always noticeably bulge when they go bad. On the back, we have nicely divided sections of PCB, with the biggest one here being the power supply, which I've talked about before. It's notoriously fragile. And there's nothing here. There's these surface mount caps, but they are fine. Again, I don't see any obvious nastiness. So I suppose at this point, it's time to fire up my dubious importer desoldering tool and start removing these things. I have previously checked that they are all correctly labeled. That is, the stripe on the capacitor matches the stripe on the PCB, except this one, which I couldn't see. But there is a plus here, and the stripe signifies the negative side, which is this pin. So that's fine. Yeah, I suppose the only thing to do is to get started. I do, however, need to record the values of each capacitor so that I can replace them with the same ones. So where did I put my notepad? Okay, got post-it notes and a pen, and the desoldering tool is hot, so let's try this one first. You know, I was hoping that this would go relatively smoothly. Apparently, it has moved a little. There we go. So, looking at this capacitor, there is some stickiness on the bottom, and I can see some green corrosion on that leg. I reckon that caps bad, and that's what the problem was. It's probably worth doing the rest, but let me get out my component tester, which is flat. Okay, I'm actually going to have to wait for the tester to charge up, so let's just proceed. So this is a 10 volt 470 microfarad, and that was C136, and that is also 25 volt 220 microfarad. Okay, so the next stage is to rummage through my capacitor drawers and find replacements for all of these. Okay, so I've managed to identify some capacitors that will work with a couple of problems, one of which is C122 over here, which is 150 microfarad, and this is the only one I could find that would work. This is the original one, which as you can see is a rather different form factor. Now I'm going to see if I can get this one to fit. It'll have to stand proud of the board, but I think there's enough space. A place where there won't be enough space is down here at C136, which is one of the 470 microfarad jobs, and the only ones I've got are these ones with stubby legs. Now I can fit it this way, but then it will be standing too high for the floppy drive to go in. So this is the original one. You see they are the same size, but this one was mounted lying down in that rectangle. So I'm going to have to do something similar, but the legs aren't long enough to actually just do that. So I'm going to have to do some creative soldering there. This thing is turned off because I'm not going to need it, so let's get started, I suppose. We should probably do them in the reverse order for reasons of access. So C120 is a 220 microfarad capacitor, which is this one, and luckily the leg layout is relatively standard, so it will just drop in. So I'm just pushing it through the holes. There we go. Flush, and it's the right way around. And I will just apply some new solder to the legs down here just to make a nice clean joint, and that should be done. Good. All right, C123 is this one in here, and that's another 220. That's this one. I do notice that the pin on the left here is marked with a plus sign, which is not right. That should be negative. I actually think that plus sign is referring to C123 next to it, but let's just find the original as 150 to 220. Yeah, the negative is the standard. So this will fit in here. These holes are actually clear, so it may just drop into place. Not quite. We're going to need some help from the soldering iron. Let's get the legs straight and solder the joints. That looks reasonable. All right, C500 over here is the 100 microfarad, which is this one. And this is a tall, skinny one, and we'll actually shorten these legs a bit. Before soldering it on, I'm going to use those wires later. Right, however, this is a thinner one than this, and you'll notice that this one has legs bent oddly, so we are actually going to have to do the same to make it fit. Let's try. That looks okay. The leg in the wrong place. Do that again. If the gods had intended humans to do this kind of soldering, then the gods would have given us smaller fingers and more arms. Okay, good. That's gone in. A bit of fresh solder, fresh solder, which is supposed to go on to the pin. Okay, there's one. That's not so great, that one. I think that has worked. Okay, C122, right? This is this one. Now, this is a different type of capacitor. It is labeled, so the wrinkly side is positive, and the side with the line on it is negative. So let's trim this down to length. So that should go on more like that. So I do wonder whether these legs are in fact too thick to go through the PCB holes. That would be a shame. Yeah, I don't think it's going to work. And the wires are too thick. Right, okay. I've got two little bits of wire there, and I've got some bits of wire here that I know will fit. So we're going to have to work around C122 here. So let's stick that one on. This, sorry, C121 here. That is a 470 microfarad. That's just one of these. That should be a fairly simple thing. Fits in there, clean solder. So now we only have these two to go, of which this one is going to be the most problematic. There is some space here, which will allow the cap to go on this way. I think what I need is some thin red and black wire, which I've got some. Is this stranded? That's stranded. I want solid. Okay, let's get a small piece. The equivalent is black and strip. That was not what I wanted. This stuff is actually quite thick. Will it go through the hole? Yes, it will. Yes, it will. So I'm going to want to solder this in place here. And this one in place next to it. Blasted things stripped. This will need clean joints, but it'll do. Okay, so this will end up over here. So let's tin this and this. Okay, now the rough side is positive. So let's just solder that on here. And then let us solder this on here. Is that a good joint? That's quite a good joint. Let's get that bit of solder out. And we clean up these connections on the bottom. That looks great. The wire slipped out. I'm out completely now. Okay. All right, so there we go. Let's do that again. Little weight of the capacitor pulled the wire out of the hole when I added the solder. Okay, so here we have our Bodger Dean capacitor. Which will sit fairly happily here. There's some, no, it won't. There's some bare contact there that's a bit problematic. But if we loop this wire around there, it will hold in there. Okay, right. One more to go. Which is the other, this one, the other 470, which has to go down there. So we're actually going to, if I can pick these things up, I'm actually going to solder in two pins sticking vertically out. And then the capacitor will solder to that. So I just want to tack this into place for now before I burn myself. Ow, too late. Turns out these copper wires, they're copper tinned with something to stop them corroding. Conduct heat really well. What a thought. The wire's not pushing through. Yeah, what's happened is the wire is wicking away the heat. So that as fast as the soldering iron melts it, it goes sticky around where the wire is. So that just needs more heat. It should eventually come free and push through. Or I lose my grip on it with the pliers. This was the one I had so much trouble with getting it out. So, okay, that is now through. That's fine, I'm at it. Let's clean this up. Gripping it with the pliers is not going to lead to a good joint. Because again, the pliers will wick away heat. But we now have enough wire in place that we can solder these. Not my best joint, but I think that will work. Okay, and now that the capacitor is holding these in place, and I can free up some hands, I can redo these properly. Except that wire actually pushed back through a bit. So, okay, that should do it. So let's trim these. The others, I think the others are fine mostly. Okay, so I believe that is now complete. So, the next thing is to hook it back up and see whether it works or not. Okay, I have it ready to work. I've been optimistic and plugged the monitor in in the hope that it will come to life. The bench power supply is set to five volts. So, I just need to plug this in, which is the right way around. We've got power, what have we got here? Oh, memory test, that looks... Well, okay, it was doing this sporadically before. So, this does not necessarily mean that it's actually fixed. But let's give it some time, five, 12, okay. There's no beeps or floppy drive noises, because I haven't plugged the speaker or the floppy drive in. So, that should be now looking at DOS. So, if I press one of these, oh, so, if I run the test 10 command, diagnostic test, no, don't test the FTD, don't test the printer, it's now doing the system board test. And it actually looks like it's working. But again, I was, it stopped doing anything. Oh, there we go. It was doing this before, okay. Video, more video, CGA, more CGA. It was sporadically working before. It wasn't just making that horrible low beeping sound. It was sometimes getting up as far as booting. More frequently it would fail somewhere along the line. One of the failure modes was it would put the cursor in the wrong place and really odd things would happen. And I haven't seen that yet. Okay, so nine exits to MS-DOS. The cursor is in the right place. What have we got here that we can run? Check disk, tree, kind of check the ROM disk, which is fine. We've got, we've got the setup program, which is not very exciting. You can't save settings on this other than in RAM. And of course, if you've disconnected the battery, the RAM dies. So you have to keep coming back to this program if you want to change things. It does seem to have worked, right to the DOS. You know, I think this may have actually succeeded. Wow. You see, you probably know whether it's succeeded because it'll say so in the title of this video. But me from the future will have written the title. Me from the now doesn't know whether it worked or not. It'd be much easier if I could look at the title of the video and figure out whether it actually worked. Unless, of course, me from the future decided to be clever and not post in the title of the video whether it actually worked or not. Okay. Well, that looks good. I'm going to put it back into the box and see what happens. Okay. Let's try it again, assembled and have a look at some floppy disks and see whether that works. Memory test, which takes a while. That sounded nicely positive. Okay. Floppy drive is doing nothing whatsoever. Maybe it's a disk. Okay. So why doesn't it like the floppy drive? It's plugged in. There is only one cable and the format command. Track zero bad disk unusable. Yeah. Floppy drive is just not working. Do I actually need to tell it to do something in the setup? No. Now, I did hear it chug when I booted it. Let's just control out Dell. Yep. And of course, it will now switch back to the internal screen so I have to do the key press to get back here. It does actually sound like the promoter is not turning at all. I have a horrible feeling. I know what might be going on, which is that this is pushing against the flywheel. So let's just reel some cable and sort of prop it up somehow. That should do it. Power back on. And of course, we now have to wait for the memory test. Can I do this now? Nope. Just have to wait. Sorry. Okay. And we boot the insert drive, insert disk. Oh no. Nothing. So it's not that at all. That looks like it's plugged all the way in. This is a non-standard connector which takes its power from the motherboard. It is plugged in the right way round. You know, it's possible that the power supply is not generating the appropriate voltages for the board and that something is wrong over here. Let me just check the connector in this end first. First has if I knew what to do next. And this is only a 720k floppy drive, which is a shame. 720k disks are increasingly hard to find. And honestly, given that this has no onboard storage and only one drive, it would be nice to have more space. Okay. So this should just unclip somehow. Okay. So this end of things looks solid. Okay. When the floppy drive, this thing is properly clipped in, that capacitor is actually not under here. So it can't be interfering with the flywheel. If I can get this actually into place, there we go. Well, now it goes round. There is a disk in the drive. It says non-system disk. There without problems. It's all plastic. So now boot it into DOS. So disk, DIRA. Oh, read failure. Oh, interesting. Very, ah, I know what's happened. Right. While working on it, I managed to bump the switch on the left. That's what's happened. This switch selects between the internal disk being drive A and the external, the port back here being printer, or this being B and the external port being external floppy drive. So now, I probably have to reboot for that to work. This should now actually, it's not going to boot off this. A, there we go. And there in fact is my compiler ready to go. Let's actually try it. So cow fee, commandel.cow to commandel.cob. That's working. Interesting thing you can see here is every time the drive does something, the light flashes red. That's because it's drawing enough current to lower the power supply voltage to the level where the battery circuitry thinks the battery is going flat. Because of course, this is plugged directly into the battery connector. Therefore, it thinks it's running off battery, but everything seemed to work. So that is good. Mandel.cob, mandel.cow, and it does the rest of the compile quite slowly. It's a very slow machine. Anyway, that all works. I'll just wait for this to finish and then put it back together again. Actually, the other thing I want to try is whether that little power supply actually works. Because currently it's connected to my bench power supply, which is running off a ATX power supply, which is kind of overkill for this. But I'm not sure whether it will produce enough current, but there's only one way to find out. Wow, this is slow. There we go. And it's finished. All right, let's put it all back together again. So here I have the other power supply attached. You throw the switch. Do a memory test. Still successfully. I don't think there's anything on that disk. It's a different one. Oh, ah, right. It just rebooted. Interesting. Yeah, I don't think that power supply is producing enough current. And I'm just going to have to use my bench power supply instead. Notice that it failed as soon as I tried to touch the disk. So let's just wait for that to boot again. Okay, watch the green light down here. When I hit the return key, that supply is not going to work. Good to know. Focus, focus. Right, I'm going to have to stick with the bench power supply then. And actually, given that I've been tempting fate, and the last time I said it was all fixed, it turned out not to be. Let's boot it up again with the bench power supply and try formatting that disk just to make sure it works. So memory test. So the disk, what happens if I try to look at it? Yeah, so my cables aren't quite long enough. But this shows the power supply voltage, which is currently reading 4.9-ish. I'm just going to get these wires out of the way. 4.93. And if I look at the disk, you can see it actually drops a reasonable amount. So let's just try formatting that. It's working. You can see the light here flickering. As it's worrying about the battery voltage. But it does all actually seem to be working. Right, I think I can call this done. And this is now functioning. I will need to keep you on the lookout for some more barrel connectors and a better 5V power supply, because I want to be able to just plug the barrel connector in the back. I'm going to drill a hole in the back plate, this, which covers the expansion slot to mount the barrel connector to. But that is a success. I am extremely relieved. So I have not been having good luck with these. One thing I want to do is to try and get one of my other Toshiba's and trace the power supply circuitry to try and figure out if it's possible to feed power directly onto the motherboard and bypassing all the horrible power supply stuff. Because that might resurrect my other two motherboards. I should also probably put the BIOS and DOS ROMs back in the test board. Which I took out in the last video and forgot to put back in again. Anyway, that is good. Just wait for this to finish. I believe this disc will fail because it's got a bad media up at the top. So let's just see what happens. Nearly finished. Seems to be happy. All right then. Thank you very much for watching. I hope you enjoyed this video. Please let me know what you think in the comments.