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G3 Lombard issues
- Thread starter techknight
- Start date
Well i decided to try this because i fixed an imac G5 isight this way, it had screen and logic board issues, random shutdowns, etc... you could just press on the logic board in a certain spot, and it would just shut off..
I fixed the logic board by reflowing it, but i still havent gotten around to replacing the screen to rid of those annoying lines. However, after reflowing the lombard's CPU card, all problems did go away. However I am going to have to get the PROPER AC adapter for it. as i cant charge the battery and run the machine at the same time. it wont charge and the AC adapter gets bloody hot.
Soon as i shut the lombard down, it charges right up.
I fixed the logic board by reflowing it, but i still havent gotten around to replacing the screen to rid of those annoying lines. However, after reflowing the lombard's CPU card, all problems did go away. However I am going to have to get the PROPER AC adapter for it. as i cant charge the battery and run the machine at the same time. it wont charge and the AC adapter gets bloody hot.
Soon as i shut the lombard down, it charges right up.
I used a basic old heat gun.
I removed the plastic rim that sits around the CPU, and preheated the toaster oven to 200deg F. yea, a little low, but significantly reduces the chance of a board warp/crack during heat.
Make you an aluminum foil heatshield to set over top of the CPU card, and ONLY EXPOSE the CPU. cut out another sheet for the bottom to expose the chipset.
Insert board in to oven and let the board preheat for roughly 10 minutes.
Remove board.
CPU side up, place your newly cut aluminum foil heatshield over top of the board, and align so only the CPU is exposed. this will protect all the vital plastic components and stuff from devastating heat.
Then take a wagner heatgun on low, held it over the IC about 3 inches away, and blasted it on low for about a minute.
Switch it over to high, and move to 4 to 5 inches away. Blast the IC for at least 5 to 15 seconds. This should do it. reseat any cracked balls.
Let it cool down for a little bit, flip it over, apply heatsheild and align to only expose chipset. Repeat the same procedure as above.
This worked for me... your mileage may vary. any time you get flaky motherboards that are newer style, this may indeed fix your issues. Newer junky PC laptops like acer, gateway, etc... all have some sort of motherboard problem, and this reflow on the CPU socket, and chipsets fixes them about 90% of the time.
Remember the ibook epidemic? yea....
Your mileage may very, as i don't have exacting equipment to measure temperatures. YET..... But we have a dedicated toaster oven that I call the reflow oven. this is what I used. I picked it up at a yardsale for $5 bucks, so what the heck.. its big enough to hold most digital boards, and small enough to use on a benchtop.
Once i get some good thermocouples i will eventually automate this. using whats called the "reflow curve" and program a microcontroller to run the oven, and the heatgun, and just make a pipe into the oven where the heatgun connects. and just line the board up with the pipe of what im gonna reflow. then the microcontroller turns the oven on, and warms it up to a proper temperature, and then blasts the heatgun to the proper temperature, and cools everything back off at the proper rate.
But yea, maybe someday when im not so busy.... OH... I use the heatgun to remove all my old SMD caps from mac logic boards. You just have to watch the plastic parts and where you direct the heat.
I removed the plastic rim that sits around the CPU, and preheated the toaster oven to 200deg F. yea, a little low, but significantly reduces the chance of a board warp/crack during heat.
Make you an aluminum foil heatshield to set over top of the CPU card, and ONLY EXPOSE the CPU. cut out another sheet for the bottom to expose the chipset.
Insert board in to oven and let the board preheat for roughly 10 minutes.
Remove board.
CPU side up, place your newly cut aluminum foil heatshield over top of the board, and align so only the CPU is exposed. this will protect all the vital plastic components and stuff from devastating heat.
Then take a wagner heatgun on low, held it over the IC about 3 inches away, and blasted it on low for about a minute.
Switch it over to high, and move to 4 to 5 inches away. Blast the IC for at least 5 to 15 seconds. This should do it. reseat any cracked balls.
Let it cool down for a little bit, flip it over, apply heatsheild and align to only expose chipset. Repeat the same procedure as above.
This worked for me... your mileage may vary. any time you get flaky motherboards that are newer style, this may indeed fix your issues. Newer junky PC laptops like acer, gateway, etc... all have some sort of motherboard problem, and this reflow on the CPU socket, and chipsets fixes them about 90% of the time.
Remember the ibook epidemic? yea....
Your mileage may very, as i don't have exacting equipment to measure temperatures. YET..... But we have a dedicated toaster oven that I call the reflow oven. this is what I used. I picked it up at a yardsale for $5 bucks, so what the heck.. its big enough to hold most digital boards, and small enough to use on a benchtop.
Once i get some good thermocouples i will eventually automate this. using whats called the "reflow curve" and program a microcontroller to run the oven, and the heatgun, and just make a pipe into the oven where the heatgun connects. and just line the board up with the pipe of what im gonna reflow. then the microcontroller turns the oven on, and warms it up to a proper temperature, and then blasts the heatgun to the proper temperature, and cools everything back off at the proper rate.
But yea, maybe someday when im not so busy.... OH... I use the heatgun to remove all my old SMD caps from mac logic boards. You just have to watch the plastic parts and where you direct the heat.
But you know, What happens when you cant buy another CPU card? Thats the way I look at things. Yes when replacing is easier, you always wanna plan for stuff like this, because nothing lasts for ever, and neither does parts. ive learned this the HARD way repairing TVs.
Example: Flybacks... Are you going to walk into a parts store and purchase a flyback for a 1951 emerson tube type tv? Are you going to walk into the apple store and get a new flyback for my mac SE? probably NOT.... Thats the next project that i plan to tackle is rewiding/making new flybacks. I already mastered regular transformers. but not IHVTs yet. There may not be flybacks for certain things anymore, but there will always be a schematic with specifications (in most cases, other cases is just plain testing on working equip), and there will always be magnet wire. hehe.
Yea, I have a lappy with a 'defective' Nvidia GPU. (remember G86 and G84 core issues from 2007?(even macbooks were affected)) and a quick bake fixed it for now.(so then I watercooled it
)A similar bake, however, did not fix my Lombard daughercard. I guess I should try a bit higher temp since I already have nothing to lose. 
no, the lombard daughter card needs some crazy heat. as did the imac G5.
but ive seen low heat conditions as you described, same with the xbox360, heat as low as a hairdryer can fix some of them, probably do to hairline fractures in the solder, and the heat causes the expansion. but itll never be correct until a full reflow could be done.
but ive seen low heat conditions as you described, same with the xbox360, heat as low as a hairdryer can fix some of them, probably do to hairline fractures in the solder, and the heat causes the expansion. but itll never be correct until a full reflow could be done.
It looks like the lombard daughtercard is working now. hehe
With nothing to lose I stuck it in at roughly 475C (my asus g2s-a1 bake was 430C and previous lombard bake was 440C) annnnnd one of the cache chips was, er, fully detached from the board.
So, meh, it is clean and I stuck it back in the lombard and it boots! It is able to boot and run Mac OS X; it was unable to before.
At this point I have been unable to verify if it is running on half cache or if it detected a chip missing and disabled the L2. I have no working HDD that I know of to stick in here so I have to operate on CDs running from a 24x TL iMac CD-ROM drive and I am limited to OS 8.6/9 and no higher than 10.3. >_>
OS 9 also did not like my 4GB HFS+ formatted USB flashdrive(that I use with my Beige G3, so it is good). :/
A mostly success! Now I just have to find out what it has detected the cache as. ..there has got to be a way to see that in OF isn't there?
*Edit
Ok, no benches but looks like no cache.. Perhaps that means it will clock up even higher! muahahahahaaa
With nothing to lose I stuck it in at roughly 475C (my asus g2s-a1 bake was 430C and previous lombard bake was 440C) annnnnd one of the cache chips was, er, fully detached from the board.
So, meh, it is clean and I stuck it back in the lombard and it boots! It is able to boot and run Mac OS X; it was unable to before.
At this point I have been unable to verify if it is running on half cache or if it detected a chip missing and disabled the L2. I have no working HDD that I know of to stick in here so I have to operate on CDs running from a 24x TL iMac CD-ROM drive and I am limited to OS 8.6/9 and no higher than 10.3. >_>
OS 9 also did not like my 4GB HFS+ formatted USB flashdrive(that I use with my Beige G3, so it is good). :/
A mostly success! Now I just have to find out what it has detected the cache as. ..there has got to be a way to see that in OF isn't there?
*Edit
Ok, no benches but looks like no cache.. Perhaps that means it will clock up even higher! muahahahahaaa
I had no idea that you could reflow with a toaster oven and a heat gun as you've described. Thanks for the info, it will definitely save me some parts in the future. I do still have my old Pismo CPU board with bad cache, maybe it only needs a reflow.
Ok, I officially need to get some nice big cache chips and attach them! xx( This is silly.
CPU:
http://poopr.org/images/o3dfzhxw25p8mhs70bw.jpg
GFX:
http://poopr.org/images/3aylm1iqqeojj5r3gx2x.jpg
Hmm... perhaps the cache chips from my old 266MHz PDQ card might do? It went down and I suspect the CPU itself was acting up and not the cache. I /should/ bake it.. but meh I already have a 300 for it. I wonder if they might be too slow. I will need to look into that I guess.
CPU:
http://poopr.org/images/o3dfzhxw25p8mhs70bw.jpg
GFX:
http://poopr.org/images/3aylm1iqqeojj5r3gx2x.jpg
Hmm... perhaps the cache chips from my old 266MHz PDQ card might do? It went down and I suspect the CPU itself was acting up and not the cache. I /should/ bake it.. but meh I already have a 300 for it. I wonder if they might be too slow. I will need to look into that I guess.
Silicon Chip magazine did a really good project writeup on setting up an off the shelf toaster oven for this kind of work. There's probably oodles of other writeups around the web.
Short version of theirs: stick a slab of aluminium in there for your board to rest on, attach an accurate and fast temperature probe (like a thermocouple and a multimeter) to the slab. Do a couple of test runs without a board in there and graph the temp vs time. If you're in luck as they were, when you turn the oven on full, it heats up nicely within the "reflow curve xxx mentioned, then when it hits the bottom of the recommended temp range you can turn it off and it'll coast up into the flow zone, peak and then cool down at about the right rate to stay inside the curve. If the delta-t strays outside the curve (or for extra geek points) add a micro to automate it.
This is also a good way to recover useable SMT components from old or dead boards, aka "bake and shake" :lol:
This is probably obvious, but I'll mention it here for future readers of this thread: once it's been used for reflow work, the oven should never be used for preparing food again. And preferably not before, either, if you can find an unused one - I don't know what the effects of vaporized bacon grease are on a PCB, but it's probably best not to find out, eh? xx(
The idea being that the board is ready at just under the reflow temperature, and the heatgun takes it up and over, right?
Pros also use a temp-controlled flat hotplate to get a board warmed up. I picked up a nice pancake maker with a flat (not curved) teflon surface, which with a bit of hacking should do the trick for that too. Amazing what you can find in the kitchen aisle }
Wow, 475C (887F)? That's some crazy heat alright. 8-o How long did you leave it in there?
well depends on the grade of solder paste they used in the factory. Some will reflow at lower temperatures and others at higher.
all depends.
but BRAVO!! at least i added some inspiration to this thread by doing something that most people wouldnt... LETS BRING THESE MACHINES ALIVE!!!! hehe
P.S. I cleaned the oven out the best i could.
Yes i use the heat gun to bump it over the reflow point. and oven to keep it just under. I do this because i dont want to reflow EVERYTHING.. if i wanted to reflow all of it, i suppose i could use just the oven IF it can get to a high enough temp. i havent tried it. maybe i should. muaaahahahhaahahah
all depends.
but BRAVO!! at least i added some inspiration to this thread by doing something that most people wouldnt... LETS BRING THESE MACHINES ALIVE!!!! hehe
P.S. I cleaned the oven out the best i could.
Yes i use the heat gun to bump it over the reflow point. and oven to keep it just under. I do this because i dont want to reflow EVERYTHING.. if i wanted to reflow all of it, i suppose i could use just the oven IF it can get to a high enough temp. i havent tried it. maybe i should. muaaahahahhaahahah
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