[quote="carlisle_united"It looks like my "new" T43 als has a bad GPU;
Does [reflow] on a T43? . . . My T43 has a metalic "cover" over the GPU thats connected to the fan[;] Will this cause a problem for the reflow?[/quote]

If the computer is "new" than you should check warranty / extended warranty status and not touch anything until you are sure you are not under warranty / extended warranty. Assuming the computer is "new" as in "new to you" and not under warranty . . .

1. Yes, the reflow, if properly done, will work on a T43. The repair is not specific to an individual Thinkpad model but to a particular part (the GPU). That problem prone part was used on more than one Thinkpad model.

2. Check out the Hardware Maintenance Manual for the T4X line. Various metal frames on the motherboard are protective structures / framework for fan, hard disk drive, etc. Remove the screws that retain them just as the HMM shows. I don't think most would recommend saving a few seconds and leaving on the motherboard any structures that can come off. My successful T40 reflow was performed on a "bare" motherboard (with a foil heat fence as shown in visionviper's photos). You should have unobstructed access to the GPU to shoot heat at it and to obtain IR thermometer readings. There are pictures and some helpful previous posts in this thread. I suggest reading this post completely if you have not already.

Correct the T43 is new to me, I bought it from a company that selles computers from companies that has gone out of buissnes. So warranty left what so ever...

The stripping down laptops part is no problem for me since I'm used to fixing and rebuilding laptops (I have never blasted one with heat though, but theres a first for everything). And locating the GPU was no problem, it's just that my GPU has a small metalic cover over the chip... Well it's the heatsink really thats conected to the fan.

I havent tried so remove this since im not that sure that its supoce to com of... So I wonder if I can leve it there while I do the reflow?

Ok... Tried the heatgun method last night but with no sucess.
I think I realised the problem after I was done, my heat gun is only an 1200W and im starting to think that it just didn't cut it and manage to produce enough heat.

SO! Im giving it a new try with... the oven.
So I have been reading looking around on the forum and the net and this has been done on ibooks with the same problem.
Im thinking of stripping it down to a bare motherboardcovering it in tin foil just like when to do the heat gun thing.
Then setting the oven to 250c... but this is where im starting to wonder.
Shuld I let the board be in the oven during the time it heats up or should I shove it in when the oven is hot.

I read in an other post in the forum that this was done by putting it in an hot oven for 4-5 min with great sucess...
But he did not cover the board with tin foil and had to resolder some conectors and stuff back.

This is what Im hoping not to do by wraping it up like a turkey.

Does this seem plasuable or a recepie to disaster?

Sounds like you did not have an InfraRed Thermometer. That is an important, I'd say essential, tool to do the reflow.

Guessing is not good enough. A specific temperature must be reached and not exceeded, and the heat must be delivered in a way that raises the temperature in a controlled and measurable manner. No IR thermometer, no luck.


I cannot speak to the success or failure of the "oven method" -- only the heat gun/IR thermometer method. A stepped progression of increased, maintained and then lowered heat (as measured by an IR Thermometer) is outlined in the previous posts here, and worked on a T40 that I can personally attest to.

Sure wish you had used an IR thermometer.

Ah I think we are missunderstanding each other here.
I do have a IR thermometer (a pretty crappy one but still) and when heating I did get it upp to a temp of 229,8c and the temp was pending between this and 228,1 for a while. But the thing is that I really don't get if the heatsink/GPU should be 230c when I temp. remove the heatgun to messure the thermerature (it was never) or if it should be that themperature when i have the heatgun pointed at the gpu and messure it at the same time.

OK, here goes...
The oven is warming up and the motherboard is wrapped up...


No turning back now.

Ok no luck...

It boots but with the same problems... And this time I KNOW that it was hot enough, I had it roasting for five minutes in a 250°c hot oven...

But still the same.., Im giving up this now.
Im starting to look for a replacement board on ebay.

-----------

And I bought myself an new board with the Intel GPU so I don't end up with this problem again.
It's a pitty all the eye-candy in Vista and Win 7 won't work with the Intel GPU, but I guess I rader have an working computer than the eye-candy...

---------

Wonder if I should have applied some pressure on the GPU during the heatup in the oven. Since I saw the soldering starting to change... Hum... I might have to do another try.

The problem is that since the T42 line there are epoxy beads (the small red dots at the edges of the GPU) to prevent warping and flexing... well kind of, but not really.
But they definitely prevent a reflow! You might read in the threads that there is no remedy, but professional firms doing it. On the T40 and T41 it was a piece of cake, with a cheap hot gun.

Aaaaaaaha...
Owell, I'll be geting my new motherboard tomorrow so I finaly can use my "new" computer haven't been able to use it proberly since i bought it over a week ago.
From time to time I start wondering if I made a bad move buying the T43 and giving my R32 to my dad.

I am having the GPU issue, but in my T43. I have it apart, have my heat gun, and am ready to go. My question is... which piece is the GPU? The original poster of this thread appears to have covered what I thought was the GPU.

The first page of this thread, the image just before the tinfoil image... There is a blue rectangle in the middle of one of the black squares. I thought this was the northbridge. and next to it, on the left, I thought THIS was the GPU. Below this (it looks like a greyish colored rectnagle inside the black square), I dont really know what this is. That is apparently what is uncovered in the tinfoil image though. I do not have this in my T43. I only have the blue rectangle thing and the thing to its left. Which is the GPU in these images??

Has anyone successfully reflowed a T43? I am certain I am having this issue, as when I press around the lower left corner my laptop works fine. Stop pressing, and it locks up.

Thanks.

The "blue" rectangle isn't blue at all. It is just how it appears due to the camera. It is actually kind of a mirror grey color.

Here is a picture of a T43. In this picture you can clearly see the CPU, the northbridge, and the GPU (has ATI on it).

One friend resolder me T40, and it's working now
I'm wondering should I glue something on graphic chip (between chip and top of laptop) so it can’t move and desloder again?

Well, not quite. As Nick (poshgeordie) has determined, you can soften the epoxy with DMF enough to remove it. However, it's apparently harder to get DMF than I (chemist) expected. It's neither particularly poisonous, nor is it an ingredient for bombs, but such things are apparently unimportant nowadays. Take a look at this thread for more information.

My T41's GPU problem escaled from occasional LCD fuzziness at certain GPU temperatures up to complete lockups at those temperatures, as well as when it was moved. I attempted a reflow earlier today, and so far it seems to have worked. It's survived multiple back-to-back runs of 3DMark 99, 2000, 2001 and 2003, but I've yet to give it a go with PC Doctor. So far so good.

The GPU in question is the Radeon 9000 32MB. I used a 1200W heat gun and an infrared thermometer. I had a surface-mount rework station nearby but that proved to have insufficient power to heat a 31mm x 31mm GPU to 230 degrees C. Hence the heat gun.

I'm seriously thinking about somehow obtaining another Mobility Radeon 9000 chip and swapping it into my X31. Now, that would be a really interesting exercise. Removing BGA chips is fairly straightforward, removing them and leaving the motherboard intact may well be trickier.

Anyway, I hope this repair holds up well. I was all about to get rid of this T41 on TradeMe as a definitely faulty machine, but now it may be worth keeping.

The T41 with an ATI 9000 is easy to fix. If your's is running fine, then you should keep it as it is resoldered. Just don't carry your T41 with one hand and you'll have years of more computing with it.

Removing and reballing might be an option on the T42. They use leadfree solder, as far as I know, which is very difficult to handle. Needs higher temperature, different flux and resoldering can easily destroy the GPU.

I did exactly as described, except the IF thermometer I borrowed was all over the place, so basically worked in blind. The worst part was putting the thing back together, I now have 20 screws leftover, and parts that are loose, but nomatternow since the thing just WORKS! and have flawlessly for 2 months now....Incredible!



I though the thing was a dead brick for sure after not knowing what temps I gave it, but sometimes you just get lucky I guess.

Anyway me and my T41 thanks you!

Hi
I have a T43p with the GPU problem. A recent reflow attemp failed and I have since discovered that a friend of a friend can perform a reball and that he lives only a few miles from my house. I was wondering if you guys can help me out with some info. I need to know how many layers the motherboard has so we can make sure we have a suitable heating profile. Also what size spheres (balls) to use? The chip is an ATI Radeon X300 216TFHAKA13FH. I've tried searching but I'm browsing with my mobile phone so it's not easy.

Any help is appreciated

Regards

Chris

The UK expert on this topic is Nick whose username is poshgeordie. Look him up and send him a PM.

Thanks Killer
I've already been in contact with him. He thinks the mobo has 5 layers but said I should get it confirmed.

You can contact Dale at GPU Medics in the US. I know he would know the answers to your questions, but I am not sure how forthcoming he'd be with the information. You can try.
There's an email the seller link in this auction.
http://cgi.ebay.com/IBM-THINKPAD-MOTHER ... 0509139459

Thanks Harry I'll give that a try.

Chris

It looks like GPU Medics don't want to talk. I've had a dam good search on the net but found nothing. Any ideas??
Its a T43p type 2668-AY5 and the board number is 39T0147. I just need to know the number of PCB layers. I'm surprised I can't find it!

Please help guys

Chris

Why would that surprise you? IBM and Lenovo have never publicly released any internal design details or schematics for any Thinkpad.

Oh I see. Well I spose Poshgeordie's educated guess of 5 layers will have to do then.

Thanks for your help Harry

Chris

Actually, the number of layers os not important as they carry heat quite easily. All you have to do is heating up the mainboard to around 120°C and then do the heat up of the GPU. 230°C for lead-free should be ok.
Check the temperature profile (google for the data). The problem are the epoxy beads. They often prevent the necessary contact because they keep chip carriere and mainboard apart. I slightly touch the melted chip with a tip and press it gently down. That seems to work 80% of time.
Tricky, but cheaper than giving up the board.

Hi

I put my board (T41 Radeon 7500) in the oven for 6 mins @ 250c with only the GPU exposed (top/bottom), the rest being wrapped in foil. I then let it cool down in a second oven switched off from 150c to try and prevent the solder cracking.

I tested it for 2hrs in the semi-built state and it worked fine. But after I screwed the case back together the same symptoms were back, freezes after a few mins or when moved.

Is there any sense in me cooking it for even longer?

First I've found that the indicated temperature on domestic ovens is not the actual temperature and can be many 10's of degrees different.

Second point - without knowing what the actual temperature of the oven is, you either do not get the board hot enough to melt the graphics BGA or the oven temperature at 250C is very close to actually permanently damaging the component substrate.

Third point - in order for the reflow to work you need to use the correct liquid flux to chemically break down any natural oxidisation on the BGA solder joints, and often not using it will not cause the solder to reflow properly or at all even when you're at the correct solder temperature.

In your case I'd say that the solder balls didn't melt and you had some point contact on the between the BGA and the motherboard which broke with the slight flexing as you reinstalled the board back into the bottom case.

I'll reply to your PM in a second.

Just a note to anybody attempting a reflow, I would highly recommend using liquid flux on the chip first.

As per this video - http://www.youtube.com/watch?v=h2R_NqF5wAc

I did this and my method of heating in the oven at 250c for 5 to 6 mins worked (so far 8 hours of testing).

I'm also considering getting a small passive heatsink to place on the video chip, to try and remove the heat that causes the board to flex.

Good one Norm - I'd suggest using a lot less flux than in that vid, since it's V flammable and can easily ignite during reflowing if you're not careful!

Re the heatsink, not sure if it will help re flexing issues; I tried a continuous epoxy bond around the chip after reflowing for a few months, and it made no difference to preventing board flexing breaking the solder ball joints again, so I no longer bother.

The real issue is that carrying the laptop by the front edge or a corner causes board flexing which in turn strains the BGA and breaks the solder joints. The best way is to carry it correctly by the sides or with the lid closed and against your side like a book.

Check out the leaflet I've done on Do's and Dont's of carrying laptops as listed on my How To's sheet in my sig.

Hi, guys!
Yesterday I've done my first try in T4x GPU reflowing - for now without success. I followed instructions visionviper wrote here, but after cooling down the motherboard the state is the same - when pressing ON button the fan spins up, but nothing more - no image on the external monitor (the laptop is without LCD for now), no beeps etc. May be the experiment wasn't clean because before reflowing the state was the same - even when pressing the GPU chip there is no image on the screen opposite to my other two T42 laptops (when I press their GPUs they work fine).
But my question is different - during the reflow process I observed that temperature measured by IR thermometer is different in different places of GPU. I found out that when red dot of thermometer's laser is placed over white characters "ATI" the temperature is lowest, when the dot is on the other places of ATI chip temperature is higher and when the dot is on the GPU's memory chips temperature is highest. The difference between temperatures measured in first and third places is about 3-5 deg/C. So, what temperature I should follow - that one measured on the ATI chip or on the GPU's RAM? I realize that the differences are due to the different colors of the places - white, black and more black, but as long as I red in this thread the temperature higher than 230 deg./C is dangerous.
And one more question - how long the temperature should be kept on 230 deg. - I mentioned the opinion that it should be kept on about 10 seconds, but no one confirmed that.