T20 Blink Of Death Circuit Questions

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Dontknow · #121 Post by **Dontknow** » Tue Mar 18, 2008 3:59 am

Tried with different batteries, without battery and using the external power adaptor, nothing changes.
It only starts after a few days of inactivity, if you leave it to rest without battery, and after holding the power button down for half a minute.

Website · #122 Post by **tfflivemb2** » Tue Mar 18, 2008 6:21 am

Dontknow wrote:A very strange problem, and if I may say this, I don't understand the total loss of interest of IBM or Lenovo about it, there are so many people having this problem, they could at least give some advice, even if the laptops are old!

The problem is that they don't perform component repair (ie. inductors, PCBs, etc.). They simply replace the whole part that is bad...in this case, it is the entire systemboard.

Sure someone has to make these boards and should know what each component is for, but chances are these board are made by someone else for IBM (now Lenovo).

Robbyrobot · #123 Post by **Robbyrobot** » Tue Mar 18, 2008 8:40 am

Sure someone has to make these boards and should know what each component is for, but chances are these board are made by someone else for IBM (now Lenovo).

What surprises me a little is that after all these years, with all the interest there is, and with the fluctuation of technicians at IBM, there has apparently never been a "leak" of a circuit diagram to the Internet. Never! In a medium where less interesting confidential information often "floats around", this is at least mildly astonishing.

Dontknow · #124 Post by **Dontknow** » Tue Mar 18, 2008 12:34 pm

When today I could fortunately start Windows on this T21, I left it on.

After a while I went to look if it still worked, and found it in sleep mode, with all the three green lights on.

I moved the mouse, pushed all the keys, but it wouldn't wake up.

Could this mean that the laptop doesn't start because it's in a very deep sleep? We all think it's off, but is it really?

Someone already pointed this out on this thread, if I am not mistaken. Or was it somewhere else?

Merlin Witt · #125 Post by **Merlin Witt** » Fri Mar 21, 2008 3:20 pm

Sounds like you could have a conflict between the BIOS and the Windows settings. I have never liked either the suspend or hibernate functions. I guess I am too impatient and do not want to wait the amount of time it takes a sleeping system to wake up, load enough of the operating system into memory and activate the resume from standby (suspend) or hibernate, load EVERY darn thing back into memory and make a picture on the screen. I played with both standby and hibernate several years ago. Both worked properly IF all of the hardware and software was configured properly,. But some of the things that go on in the background when a computer is powering up require such strict timing controls that it was easy for someone to not have everything exactly as it had to be to work properly, OR add a new piece of hardware or software that interrupted everything.
After reading as much as I can find on the BOD problem, I have come to the conclusion that there are several completely different problems that provide the same feedback to the user.
All of the problems are related to how the boot device (whatever it is that is used to sequence the CPU differentiates between internal and external power sources. After investigating one of my T23's, I have the following observations.
1. There are five possible power sources to the main board.They are AC charger, Docking Station, main battery, Ultra-bay battery and the CMOS battery.
2. The main board is a ten layer board. There are eight internal layers from my count on the edge of the board, plus the top and bottom layers.
3. The board was manufactured in Malaysia OR Taiwan. The board is silk screened Taiwan, but has a Malaysia sticker .
4. IBM provided the board layout. The copper etch has IBM as does the silkscreen.
5. There are at least six (6) different voltage sources on the main board. There are four toroids on the top and two on the bottom of the board. These will provide at least one voltage level each.
6. The board design has been changed at least once.My board is a revision one board. It was manufactured during the eighth week of 2002.
7. There could be as many as 15 different fuses on the main board. (I was unable to locate more than eight, F1,F2, F4, F9, F10, F11, F12, F15. F2,F9, & F 10 are high current fuses for a computer motherboard. They are rated at more than 7 Amperes.

The Docking station and AC charger share fuse F2. F9 & F10 are for the battery packs. I have not traced the other fuses, but all of the fuses on my motherboard measure good.

Please be extremely careful when checking fuses, I have found fuses as small as 1/16 Ampere. An Ohmmeter with a 9 volt battery will ALWAYS check one of these fuses as bad. The Ohmmeter blows it unless a 1000 ohm series resistor is added between the meter and the fuse.

More later, My T20 BOD'd and I want to see if I can get it back on.
Merlin

Dontknow · #126 Post by **Dontknow** » Sat Mar 22, 2008 1:08 pm

Hi Merlin Witt, just wanted to thank you for the job you are trying to do. Hope you find more about this annoyance.

As for me, I'm not such an expert on laptops, my speciality is desktops, so I can't find out by myself what is wrong with the thousand boards showing the BoD.

As a last resource, tonight I bought a new motherboard on e-Bay, certified 100% working, in a few days I'll let you know if it really works or if I have to use the two weeks warranty to return it.

In the meantime, I can start my T21 every day, but if I turn it off I have to wait for next day. Not interesting for my grandson, who has to use it every day. I also disabled all hibernation, sleep, or stand by, normally I never use them , that's why I was surprised to see the half moon on when I couldn't start up again a few days ago.

To be continued...

okayman · #127 Post by **okayman** » Mon Mar 31, 2008 9:44 am

Dear friends of Thinkpad forum,

I'm happy to learn from all of you about how to do fixes and replacement in the circuitry. I've posted a question about power supply, here:

http://forum.thinkpads.com/viewtopic.php?t=59577

Would the cause of BOD, caused by high current than the designed current input?

I've checked the power supply adaptor spec and also the laptop spec at the bottom of the T20 and T21 (now BOD).

Power supply reads: 16V 4.5A
Label on Thinkpad bottom: 16V 3.36A

Would this be a likely cause for the "accelerated aging" of ICs on the motherboard? I really wanted to see not just fixes, but also to prevent it from happening again. Pros and Engineers, any advice?

Thanks!
Felix

Merlin Witt · #128 Post by **Merlin Witt** » Tue Apr 01, 2008 2:08 pm

Not really. A power supply is typically rated by the amount of current at a specified voltage that the supply can provide without exceeding the other specifications of the supply. Specifications such as Temperature, output voltage ripple, output hum and noise etc. A power consuming device is typically rated by the maximum amount of current required to activate all internal circuitry in the device at the specified input voltage. In a computer the maximum power consumed will change due to many factors. Is the hard drive powering up or idle? How busy are the Central Processing Units? How many USB devices are attached? And in the case of a laptop or notebook computer, what is the state of the display.

I am sure the problem is power related, but not sure where to even start troubleshooting. I have been experimenting with my T20 and have not been able to get consistent results other that turning it off for several hours with all power sources (except for the CMOS battery) removed. If I do this then I can always get it to power up by holding the power switch down while inserting the AC charger / adapter. At least part of the problem is that the power on sequence for modern computers is so fast that without knowing EXACTLY what happens and when it happens, makes troubleshooting more of a trial and error effort as compared to any of the standard troubleshooting techniques.
There are three possible external main power sources on the main board. The power connections between the main battery power lines and the Ultra-bay power lines do not appear to be the same. Each power source (AC, internal battery or Ultra-bay battery) has it's own 7 Amp (or higher) rated slow blow fuse.
This tells me that there is a difference between the battery power on sequence and the AC power pack power on sequence.
The time delay between the pressing of the power button and the blink of the LED seems to be constant, but without a dual trace storage scope, one can not say for sure.
My best guess at this time is that either something is drawing excessive current from the battery power source lines , and the internal power protection circuitry is disabling an internal watchdog timer which is not letting the CPU power up, or the battery pack communication to the power up sequence is causing the overall power on sequence to fail.

Does the BOD problem occur with an Ultra-bay battery installed?

chilipuca · #129 Post by **chilipuca** » Wed Apr 02, 2008 10:01 pm

I also have a T20 with the BOD problem and I am also reading a lot of coments on severals forums (including this) about this issue.

Somebody said (another forum) that the problem is related to a overcharging battery with the AC adapter... so I ask you guys... could this be the origin of the BOD problem?... if not specific on overcharging the battery, but overcharging the mobo or another of its components.

I have seen this behavior: When I turn on the system with just the battery attached, using it only with the battery, and finally turn it off only with the battery, the systems seems to boot fine the next turn on.
But if I use the AC adapter and leave the system full charge the battery (maybe overchargin it), the laptop wont turn on unless I leave it for a long period with all the power sources disconected.

The system also turn itself off if I disconect the adapter after leaving it the cord plugged in for a long period beyond the 100% of charge... something like the battery if overcharged and the system detect it shutting down the system to protect itself.

So what I do to ensure to properly turn on the system when I want to is, not to leaving the AC adapter pluged in to the laptop and even not full charge the battery (not 100%) and of course avoid to leave the system with both the power source connected, because on this situation the battery will keep on chargin even with the system turned off.

At this point, considering that sometimes by mistake I leave the Ac adapter charging the battery and I forgot to disconect it before the battery reach the 100%... could I use some kind of method or software to avoid the battery to full charge?... something like 95%?

I know this will not fix the system... but at least make it full usable.

chilipuca · #130 Post by **chilipuca** » Sat Apr 05, 2008 4:58 pm

Thinking again about how to fix this issue

Could be possible to make some kind of reset circuit on the motherboard? I mean, something like a micro-switch connected somewhere on the mobo, for example to full discharge a capacitor or to reset the error condition on maxim chip?

This way, we could just push the reset button each time we want turn our laptop on

Am I wrong?...It's an stupid idea?

A little help here please

Merlin Witt · #131 Post by **Merlin Witt** » Sat Apr 05, 2008 6:40 pm

Of course it is possible to add a micro switch to almost anything. Actually, the power on switch on most laptops is a micro switch. The problem is there are too many unknowns at this time to tell exactly where such a switch should be located and if such a switch would work.
I just dis-assembled my T20. My T20 motherboard is very different from my T23. My T20 has four DC to DC converters (Power supplies) on the top of the board. It has none on the bottom. My T23 has three on top and two on the bottom. Each power source will have at least two associated capacitors. Which one of these is the culprit.? If in fact one of them is the culprit.

ALL Central Processing Units require the staged application of power and an external clock source. These functions happen before the CPU can process anything. The CPU must read a configuration file that sets the CPU start process. I am not familiar with the EXACT power on sequence requirements of the Intel Pentium series of CPU. But, the configuration information I am talking about is NOT the CMOS information we can change. The configuration information is stored in ROM and would through external devices control the application of power to ALL of the individual power sources on the board.
The devices I am talking about are normally powered by the primary sources to the board the battery(ies) and AC charger / Power sources. I think that something in this power on sequence is stopping the CPU from powering up. I also think there is something in the power on firmware that is either not providing the proper sequence of events to the CPU or it is telling the CPU that there is a problem with the power source(s) and the CPU is refusing to power up.
This something could be data from a discharged / overcharged battery that changes something in the CMOS battery information that we cannot access. It could be as, many people suggest am open circuit on a capacitor. It could be a problem with the Zero Insertion Force socket that normally holds the CPU. If there is a problem with this socket, which is located under the left rear corner of the keyboard, there is no easy way to determine the effect on the CPU. I have read a lot of posts about this problem and Flexing the left rear corner of the housing could be necessary simply because the CPU has a dirty or loose pin. Flexing my T20 has no affect on my T20.

chilipuca · #132 Post by **chilipuca** » Sat Apr 05, 2008 7:17 pm

You are right.
The idea of an reset switch comes from the idea that max1632 have something to do with this BOD problem and particularly the internal protection circuit mentioned at the beginning of the thread... and then a way of reset the possible estate on this circuit.

okayman · #133 Post by **okayman** » Sun Apr 06, 2008 11:04 am

Thanks guys for all your descriptions and input about the BOD symptoms. I have read and re-read this post many times and trying to analyse what is the real cause.

Same as you guys, I'm not sure, but I wish to ask, did anyone tried to just replace the CPU? Does it work on a supposedly BOD board?

The reason I ask this question is:

1. In first few post, evo4jon and others have tried to replace a few apparently good motherboards but after a while, all of the boards being replaced also showed BOD. Can't get them back to work afterwards.

2. For those who have replaced the adp3421 or maxim chips, also are not 100% working solution.

3. Maxim chips circuit protection - I have a hunch that this is not the root cause. If their protection behavior is "stored" by a/a few capacitors, leaving the board without power for months, should be able to deplete the stored power and supposed to reset whatever the "protection data" in the maxim chips. But this also seemed not the case.

4. Power on methods - with AC supply, battery alone, or any combination, seemed to have no effect. Also, the "draining" method also don't seem to work here.

5. Faulty capacitors - those may be a cause of this BOD problem, but as none of us have a schematics of the T2x board, it is really hard to check, really hard.

My father once told me 20 years ago, using a good capacitor will maintain stability and functionality of most electronic circuits. I still remember this. So I wouldn't rule out this would be the cause.

Also, the T2x series has been aound for 7-8 years, any components inside the board could just be time to develop aging and component failure, experienced overheat problems even once or twice in the lifetime (such as someone putting in in the bed and watch DVD, etc).

What I will try is to find a known working CPU and mobo to test (1 set of both known working CPU and mobo, and 1 set of BOD mobo and the CPU used to be in the BOD mobo), swap them around. Just try to test if the CPU will cause the failure of other component (such as the suspected Maxim/AD chips). If anyone have tried this, please let us know the result, it will greatly help. Thanks!

okayman · #134 Post by **okayman** » Sun Apr 06, 2008 11:55 am

I'm now reading the datasheet and errata from Intel's website about Mobile Pentium 3 processors.

Some interesting read as well. Some of the ERRATA mentioned in some "Stepping" models of some CPU:

Errata K7... I/O restart in SMM may fail after simultaneous MCE...
Errata K9... MCE handler may not always execute successfully...
Errata K1AP... APIC access to cacheable memory causes SHUTDOWN...

FYI, I've checked the term SMM and MCE, they represent System Management Mode and Machine Check Exception. You can checked on Wikipedia for both terms. Very interesting read by the Intel P3 spec sheet, as some problems on some processor models WERE NOT FIXED.

Especially Errata K7 I'm concerned of, which sounds like the BOD thing. Anyway, I'm not too pro in reading those terms, but anyone interested please check if there's any relation of the CPU behavior and other components.

Intel Mobile Pentium 3 Specification Update:
http://download.intel.com/support/proce ... 530659.pdf

I'll try my best to test things out, but I can't work alone.

matthewpoer · #135 Post by **matthewpoer** » Mon Apr 14, 2008 4:43 pm

I am also receiving Blink of Death symptoms on my T21. The problem for me has been seemingly random, but I think that I have found a trend: the BoD appears after the computer has been plugged into an outlet and charging for a long period of time. For me, this was about 24 hours last time and perhaps longer the time before.

My time line is currently this:
24 hours charging w/ battery, powered off.
42 hours unable to boot (BoD)

In the past, it has seemed like time is the consistent factor for the BoD to go away.

I have taken my T21 completely apart to look for any obvious problems and have not seen any. I will soon attempt to reflow the solder as proposed by evo4john, as I believe my BoD is also caused by power-flow-type problems.

UPDATE
after ~50 hours of not being able to boot, I disassembled the T21 to inspect it. I found nothing obviously wrong and let it sit overnight, which puts it up to around 60 hours of not working. I assembled the next morning and it worked. I was able to use it for about 2 hours, once the battery died I let it run with battery and plug-in for around 45 minutes. Then I turned it off. An hour later I went to turn it on again and received BoD. I removed the power plug, battery, and 3v.

About two hours later I tried again, this time pressing the power button repeatedly, and after 20-30 attempts the T21 powered on as if nothing had happened.

I think that this signifies that whatever electrical circuit that is mis-handling power inside my laptop is getting worse.

Another UPDATE
Immediately after posting the above, I turned my computer off to see if it would BoD again. It did. I had been running for less than 10 minutes off of the battery (no plugged into the wall) before I powered it down. I removed the battery and 3v for perhaps 5 minutes, then got an idea. I put the 3v back in, left the LithIon battery out, and plugged it into the electrical wall outlet. I turned it over and pressed the power button and the T21 came on.

This raises my suspicions toward my battery. It is not a typical IBM battery, it is an "extended life" enhanced battery from
BatteryRefill.com. Inspecting the battery itself, I can see that the seal/glue that they used to put the battery back together (after replacing the cells) is wearing in most places and gone in others, and I think that I could pull it open if I tried. Could this super-battery be the cause? I am will try to run strictly off of the power cable and see what happens.

AND MORE
After running the T21 for about 20 minutes on power-plug with no battery, I turned it off to check for BoD. It did have BoD. I unplugged and left battery out. After around 30 minutes, computer was able to boot with power plug. I observe that battery vs. power plug is not a significant detail at this point in the problem, and that the 3v backup CMOS battery should have no effect on BoD or BoD recovery.

However, I still wonder if the super-battery may have caused the initial damage. I do not know a way to test for this.

matthewpoer · #136 Post by **matthewpoer** » Mon Apr 14, 2008 5:02 pm

Dontknow wrote: Removing all power, waiting for a couple of days, pushing the power button for half a minute, then inserting the battery will make it start up again.

Does it help if you are wearing a funny hat, flowing gown, and dancing a jig around the machine?

Geez IBM! What kind of voodoo do these machines require?

But really, there must be a formula to making this work. I have decided that this is a power problem, whether some capacitor is defective or some chip hogs the power or what, I don't know, either are possible and could be caused by age, I think.

Also note: the battery in my T21 is one of the "high-capacity/longer life" ones from eBay. Anyone else?

Dontknow · #137 Post by **Dontknow** » Wed Apr 16, 2008 4:02 pm

Ok, that's final now, my BOD T21 is cured, I replaced the motherboard with a new (tested working) one I bought on eBay for $30 plus shipping and everything works again as before, with battery, with ac adapter or with both inserted.

Now I'll keep an eye on it, and hope the BOD doesn't return in a few days.

I'll see in the next days if I can find any differences between the new and the old motherboard and let you know, but something tells me you all already looked for that.

Oh, I forgot to mention I also replaced the processor with a 1Ghz I had here in the house, if Okayman was right I wouldn't get the BOD again.

If I find a docking station I can try to tmake some tests with the old motherboard, the one with the BOD (I still have two processors lying around)!

nikki605 · #138 Post by **nikki605** » Wed Apr 16, 2008 4:22 pm

Replacing the motherboard was the only thing that fixed my BoD T21 after trying to tinker around with it for several months. The eBay replacement from lady_fixalot I installed a year ago is still working (knock wood).

I also put a 1GHz (SL53S) CPU on this new board with a dab of AS5 and a T22 fan, as the members here recommended.

Msmax · #139 Post by **Msmax** » Sat Apr 19, 2008 4:12 am

I still think this BOD problem is related to one (ore more) of the switching mode power converters om the mainboard, because next steps did not solve anything:

- replacing power supply
- battery
- RAM
- Modem/LAN cards
- CPU

I was able to get a few mainboards back to live by replacing the ADP3421. Then on others this replacement did not solve anything, so another SMPS was failing probably. It is also known that a bad batch of these chips with a high failure chance were produced and used in notebooks. Also some other brands have problems like this and they have also this chip inside to generate the VCore.

It is a known problem with SMPS that capacitors wear out due to the high swithcing frequency of the chips. This has been recognised (and repaired by myself) in:
- TV's
- Video Players
- CD/DVD Players
- Desktop PC's.

For example:
Occasionally my Desktop PC had a strange behaviour.
- Keyboard did not work, unplug/replug keyboardsolved the problem partially (reversed operation of CAPS button...)
- No powerup, after repeatedly trying it would power up.

All these problems were found to be related to a small capacitor in the power supply unit which was there to stabilise/filter the 3.3V output.
Replacing the capacitor did solve all problems for 100%. The desktop machine is still running now for 3 weeks after the repair without ANY problems.

As I moved to T23/30 machines, I will not work anymore on the BOD problems of the T21/22/23 notebooks. For all electronic engineers out there: have a close look to the different SMPS's on the mainboard. Download the datasheet where you will find example schematics. Almost 90% of the IBM design will follow this schematic.

Msmax

matthewpoer · #140 Post by **matthewpoer** » Sat Apr 19, 2008 8:34 am

I have been thinking "capacitor" to myself for a week now. It is as if the circuitry has aged to the point where it is defective.

To update on my situation, I am now able to to predict when my T21 will BoD and when it will work.

Essentially, if I use the computer for any amount of time, and turn it off, it will BoD immediately when turning it on. However, after removing the battery and power cable, and waiting for 3-12 hours, the machine will boot with no problems.

The "time" factor is what makes me think capacitor - it's as if power has to slowly drain. The odd aspect is that attempting to power the machine with no power source does not drain these theoretical capacitor, and I cannot determine why.

As for the CPU problem - I don't think that the BoD is CPU-related. When I stripped my machine down a few days ago, I put the keyboard/LEDs on the mainboard and plugged in the battery (there was NOTHING ELSE, no cpu/cards/minipci/ram etc), the machine returned BoD symptoms.

And for those who simply replaced the mainboard - I am very happy that your machines are working. However, I don't think the problem is solved. Clearly, these mainboards are, in many cases, defective. While I hope that your "refurbished" boards do no BoD, it is likely that they will in time.

At this time I do not expect to attempt to reflow any solder. It does not seem to me that this is a factor. I will look into Msmax's situation.

Dontknow · #141 Post by **Dontknow** » Sun Apr 20, 2008 5:51 am

Yesterday I ordered a port replicator, when it arrives I can begin making tests on the two BOD motherboards I still have without having to mount and dismount everything all the time.

To be continued...

obpsym · #142 Post by **obpsym** » Mon Apr 21, 2008 11:11 am

Just joined the club, my T22 has the BOD,

Last operation was a few days ago running an external display via the port replicator, it was set to sleep.

I bought an after market battery for it a few months ago, don't know if it's connected to the problem (overcharging?)

nikki605 · #143 Post by **nikki605** » Mon Apr 21, 2008 12:20 pm

I never had a port replicator for my BoD T21 and I am still running the same battery before the problem started as after the problem was fixed. Replacing the motherboard fixed my BoD. But, we kinda already knew that.

obpsym · #144 Post by **obpsym** » Tue Apr 22, 2008 3:36 am

Well, the good thing about the port replicator is that you can power on without the keyboard.

I removed all the drives, memory, Ethernet/modem, CMOS battery, Keyboard and tried to reset power with and without mains.

After a few minutes I gave up, rebuilt the T22 and lo and behold it powered on without the battery but hung at the login screen.

I hard reset it and set the correct time and date but still hung at logon, next I set the speed-step option to max power and it booted fine. Installed the battery and tested a reboot, power on and off are ok.

Guess it will probably die again shortly, but my feeling is that the after market battery could be messing with the power management / capacitors somehow.

anyone with an original battery with the BOD?

matthewpoer · #145 Post by **matthewpoer** » Tue Apr 22, 2008 2:45 pm

obpsym wrote:Well, the good thing about the port replicator is that you can power on without the keyboard.

I removed all the drives, memory, Ethernet/modem, CMOS battery, Keyboard and tried to reset power with and without mains.

After a few minutes I gave up, rebuilt the T22 and lo and behold it powered on without the battery but hung at the login screen.

Oh, I know that feeling...

obpsym wrote: ] Guess it will probably die again shortly, but my feeling is that the after market battery could be messing with the power management / capacitors somehow.

anyone with an original battery with the BOD?

A very good question. So good that I just created a poll for it.

Merlin Witt · #146 Post by **Merlin Witt** » Wed Apr 23, 2008 7:02 pm

I have five different batteries that show the IBM silk screen, but were manufactured by SANYO. They have ALL been in and out of MY T20 that BOD's. They work fine in my T23 and No BOD there.

matthewpoer · #147 Post by **matthewpoer** » Tue Apr 29, 2008 3:12 pm

Okay, not the problem.

Here's something to add, though:

After using my T21 on batter and on/off power for a very long time (about 2 days of having power on), and then turning it off, I found that I can boot it back up within a small amount of time.

But, if I then let it, say, charge the battery for an hour while power is off, and then I return to use it, I recieve BoD.

So why does it not BoD if it has been running for a long time a short time ago?

Dontknow · #148 Post by **Dontknow** » Tue May 13, 2008 5:59 am

Ok, I finally found the time to run some tests using the port replicator I bought for 0.95 from e-Bay.

As I already said, I have two T21 motherboards with BOD. I solved my problem replacing the motherboard in my T21 with a third one, that now still works perfect.

So I took one of the two motherboards with BOD, I placed a processor with cooler on it (fixed it with two small screws to the motherboard), put a SO-DIMM in place (only 64 Mb I found in a drawer), attached a small hd (3 gb) with windows Xp on it, pushed the whole thing into the port replicator, connected mouse, keyboard, display and ac adaptor to it and powered on.

Well, I've been powering on and off for a long time now, and it always starts, without BOD. Of course I have to reenter the date and time every time, because I didn't attach a CMOS battery, but every time I push the power button I can start up.

I could almost never start before, when this motherboard was installed in my T21.

I leave to the experts to take conclusions, but I think that BOD has something to do with the battery or the connections between the power adaptor and the motherboard. Otherwise I don't understand why this motherboard, which never started up before, starts now every time.

I can't test the second motherboard, because the password chip is missing on it, the earlier owner must have needed it on another Thinkpad.

I hope this can be helpful for brighter people than me.

furiousmonkey · #149 Post by **furiousmonkey** » Wed May 14, 2008 10:13 pm

Let me get this straight, and please let me know if anyone has had any success solving BOD with a DOCKING STATION.

I have a T21 Motherboard with 800mhz that I have sitting in my basement for the past year and a half.

When I figured that it had the BOD problem I just purchased a T23 Motherboard and plastic housing and "made" it fit with my T21 top and screen. The only draw back is when I went to Thinkpad website to update my drivers, I hit auto detect, it could not figure out what the hell I had "under the hood" but it gave me abc0-001 and from that I was able to make my own judgement and even update the BIOS.

Now I am running 1.13ghz but I wanted to build a computer for my car with the 800mhz, I just happen to have purchased a couple of docking II replicated for $12 can. each!

This sounds like a pretty good thing

Dontknow · #150 Post by **Dontknow** » Thu May 29, 2008 4:51 am

After a couple of weeks, during which my motherboard, mounted on a docking station as explained before, did work without showing sign of BOD, we are back as before, no start up when I push the power on button.

I can't check if the hd light blinks as there is none installed, but I think it would be so, if one was present.

So the cause must be searched somewhere else on the motherboard, and not in the battery or ac adapter as someone suggested.

BTW, no new findings have been posted in 14 days; does this mean that everybody has given up?

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