I finally got myself a mostly working 701C and successfully rebuilt the battery - except it has one issue. Randomly (and seemingly, often) the mouse pointer just dies. The only way to get the mouse working again is to hibernate and wake it up again. I tried using an external mouse, but it suffers from the same issue, even when turning the TrackPoint off. If anyone has any ideas for the issue ... otherwise ...
I see on eBay, there seems to be 3 different top motherboard models listed for the 701C. There seems to be:
I'm thinking of purchasing one to replace the top motherboard on my 701C, to hope it solves the mouse pointer issue, but I was wondering if there are any 701C experts around that know the differences between the different part numbers.
I'm curious if some of them are a later revision with more 'fixes', which I assume I'd prefer ...
Thanks for any info,
Hmm, why do you doubt that is the issue?
As far as I can tell, the TrackPoint interface circuity and calibration circuity all seems to be on the top board, though I could be wrong.
It seems to randomly fail when it hasn't be used for x amount of time, and can be reset when sleeping/awaking the unit, so I assume there's something wrong with some part of something to do with the calibration ... which I assume is on the top board?
That's my guess, at least.
If one of you wants to sell a top board I'd be willing to buy it from one of you rather than eBay
Hmm, definitely not a software issue. I was wondering that at first, but it seems to depend on the temperature of the unit, and it's not just restarting that will 'fix' it. I was going through the HMM and came across this:
So, I decided to 'suspend' and then 'resume' the unit, and bam it comes back. And then shortly dies again. Suspend and resume its back ... leave it alone for a few minutes, bam it's dead.Note: The TrackPoint III performs automatic
compensations to adjust the pointer sensor. During this
process, the pointer moves about the screen for a short
time. This self-acting pointer movement can occur when a
slight, steady pressure is applied to the TrackPoint III
pointer when the computer is powered on, when the
system is running, or when readjustment is required
because the temperature has changed significantly within a
short period of time or the temperature is higher than its
operating temperature. This symptom does not indicate a
hardware problem. No service actions are necessary if the
pointer movement stops in a short period of time.
However, the TrackPoint III will not stabilize if you apply
pressure to it. If pointer movement occurs, you can go into
Suspend mode, and then resume normal operation.
Resuming or turning the computer on both cause the
TrackPoint III to be calibrated, which may correct the
problem. If you see continual movement of the pointer, the
TrackPoint III is probably defective. In rare cases, the top
system board can also cause this problem.
After restoring the battery I did update the BIOS to the latest, so I don't think it can be an error there. I also attempted resoldering all the components around the TrackPoint circuity on the top board in case it was just a cold solder joint, but I'm unsure what component actually performs the calibration routines (which I assume is what is actually somehow causing the failure). Didn't get better, or worse, but it's annoying.
For now at least, an external mouse works fine, if you disable the TrackPoint in the BIOS (otherwise the external mouse dies as well). But since the HMM says the top board, I'm hoping a new top board will fix it ...
Anyway, if one of you think I'm partially making sense and want to unload a top board, just PM me with a price.
Also as an interesting note, even though both boards are marked "IBM FRU 04H8343", they are slightly different. There's probably a revision code somewhere on them, but I'm not opening it again.
The boards have (at least I noticed at a glance) some slightly different capacitor arrangements, and the 'original' board actually has a jumper wire connecting to a transistor jumpered to the board (obviously a stock job), as well as another jumper wire between a resistor and cap. The new board has neither of these. Plus, the new board has a "PRESS HERE" silkscreen where the connector to the bottom board is, while the original was lacking one.
I guess there was more than one revision of 04H8343.
Now to install the 1 gig PATA SSD I got, and learn how to install Win95 with a PCMCIA card CD drive
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