Baking Graphics card?!

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nuclearmass

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Aug 12, 2013
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Upon doing research and having a broken gpu, I decided to "bake". However, my gpu is permanently unusable as the capacitors fell out of the pcb. I had a bad feeling about having the card face downward, but that's what all of the "tutorials" said to do, so... Wth did I do wrong?! I didn't run into this issue when researching?
 
Baking a GPU is temp fix AT best, and everyone oven is different in temps, hot spots, etc. I wouldn't have done it upside down as gravity would pull parts out, exactly what happened.

Basically, all electronics nowadays have lead-free solder. This is so when old electronics go to die, they end up in a landfill and the lead doesn't leech back into the water table, etc. The problem is, lead-free solder sort of sucks. It can break easily under heat stress, it develops what are know as "tin whiskers", etc. When this happens, you can either remove the chip and replace the solder balls using a stencil and lead or more lead-free solder, or try a reflow, which is to drench the chip in flux, and then heat it up so the cracks could seal up, the tin whiskers would get sucked back into the balls, etc. Most lead-free solder used in electronics starts to melt and become liquid at 217 degrees. EXACTLY. You can heat it to about 222-224 degrees and that's it. You keep the heat at that temp applied for about 20 seconds, which is called the dwell time. Then you let it cool. This is what causes no-video on laptops, the Red Ring of Death on the 360's, the Yellow Light of Death on the PS3's and most electronic failure involving BGA chips. I have fixed thousands of laptops, 360's, PS3's, TV circuits, etc, all using a professional reflow machine that costs me about $2000 plus supplies.


Now, people who don't have a computer controlled temperature monitored reflow machine, think, heat, oven, toaster oven, hair dryer, paint stripper, etc, can do the same thing. It can't. My machine slows ramps up the top and bottom temps of the board and monitors the temp of the chip itself to eventually get to 217-222 degrees for 20-30 seconds, then stops. An oven doesn't. A paint stripper doesn't. None of the "youtube" fixes do. It's almost impossible to put a board in the oven and keep it at EXACTLY 217-222 degrees. Oven/toaster oven/paint stripper fixes usually fail. It heats up the chip, but in no way, shape or form, does it "reflow" the solder to becoming pure liquid solder.

Considering you heated up your card enough to get all the solder liquid to the point that caps are falling out, you probably hit way hotter temps than the 217-222 window, and probably toasted the GPU itself, if not other components.

Sadly, YouTube is not the pinnacle of human knowledge, just people with a camera.
 

nuclearmass

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getochkn, thank you SO much for the clarification! I really appreciate the huge effort you put into your answer. I wish I would have posted something on Tom's before baking, but then again, the gpu was dead in the first place. I really shouldn't be that upset about it... Maybe because I saw other people profit from the baking.

Anyways, I have a reason to clean my oven now!
 

Kari

Splendid

I got couple of problems with what you said
1. several lead free solder alloys have better thermal fatigue properties than eutectic tin-lead.
2. typically components can withstand temps up to 250-260c, ceramic caps even higher.
3. most lead free solders arent exactly eutectic so they dont have exact melting point, rather a window where the solder is more or less partially molten, and you should go like 5-10c above that window (at least) on the coldest joint on the board to get proper joints (without cooking the components on the hottest point). 217-222 is typical temperature window a solder melts in, so 228c would be a good point to aim at.

and the machines we use at work cost way more than the hobby kit you have :p


anyways it wasnt really smart to place the board 'face down' like the op did, when the solder melts there isn't much keeping the heavier components in place anymore, there is a limit what the surface tension can hold up...
 


Yes there is other lead-solders. The most common used in most consumer electronics I find will melt and you lift the chip with full liquid solder and not lift a trace at that temp window, plus or minus a few degrees.

Yes some components can handle those temps, some can't. Get a 360 GPU up to 230 and it will bubble on the top and delaminate and be toasted.

I tried to give a basic description of what a reflow is to the poster to show the difference between an oven reflow and a proper reflow, not get into specific formula's of solder and each of their melting points.

Thanks for taking a knock at my "hobby" machine. Obviously you work in some sort of electronics field, so I would expect you would have better machines. For my use, it works. I can lift a chip cleanly, reball the solder balls, and reattach the chip back to the motherboard.
 
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WickedGirl

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getochkn, while this thread was 9 years ago, I came across it today, and you made perfect sense to me. Your information just helped me immensely. Thank you!
 
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