Liquid flux in kitchen owen

[Kemer]

I will heat a graphics card in kitchen owen and will use a little liquid flux on it. I probably won't use that small owen for cooking pupose but want to ask if someone tried the same thing. Thank you.

[DynaxSC]

I can tell you only not to do this!!! This is completely unprofessional. You have many parts on the board, eg. electrolytic caps, plastic parts, which by far do not tolerate temperatures needed to make the tin under the GPU liquid (unleaded tin has a melting temp of 254 C, so you have to heat the owen even 20-30 C more). Even if the board will survive this torture you may have with big luck an effect of working card for a few weeks, then failure will come back. The price will be dramatically reduced life expectation of the card. You also risk displacement or falling off of parts, as you make this way all the parts on the board having liquified tin. Electrolytic caps can even explode in such temperatures, they have usually 85C tolerance. If they explode they will blow off any parts in the direct neighbourhood. Any paintings on the board can change color, white will get yellow or grey, etc. You can destroy your card this way, and the chance to repair it with this brutal way is very low. Better give it to some professional for repair. Also the reflow of the GPU balls, even with flux, is in most cases unsuccessful. Also you must use a very good flux for reflow/reballing, 99% of the fluxes available in electronic shops for hobbyists is not suitable for chip reballing and reflow refitting with unleaded tin. They will not withstand the higher temperature needed for unleaded tin and will evaporate or turn to burned residuals before the tin is liquid, not making the job. Here only industrial fluxes with special additives make the job reliably. Only reballing GPU and memories with dedicated tools like preheater and hot-air gun is the right and reliable solution.

[Kemer]

Thank you for your time. I really grateful. This is only a MXM-2 type standalone GPU card for a laptop. I have tried to heat in owen (~200C) but failed. Then a professional saved it with a BGA heater but for 4 months. Approx 4 times BGA reflow will cost a card. So I wanted to try it again with a liquid flux. If I failed, won't try again, else happy end. But I definetely won't as high 254 C temps. Anyways, I appreciate the experience, knowledge and equipment of professionals. That's why I'm here.

[piernov]

A dead GPU is a dead GPU. A reflow won't magically fix it. Sad that the misconception still runs free in 2024, more than a decade and a half after Nvidia bumpgate…

https://www.badcaps.net/forum/troubl...es#post1459061

2.1. Never reflow large BGA
It won't fix the problem since 99% of the time it's not an contact issue between the BGA and the logic board. There's a high risk of damaging the board even further.
If you want to confirm if an AMD/NVidia chip is bad, you can heat it up to 200°C max for a minute and a half, no flux. It'll come back to life for a short while and then die again, because it's bad. In this case it has to be replaced.

https://www.badcaps.net/forum/troubl...vidia-bumpgate

[DynaxSC]

Yeah, but there are some people out there, who do it, and if the card start working again they sell them immediatelly as long as they work, and get rid of the problem. The buyer is then pissed off one week later.

[Kemer]

A dead GPU is a dead GPU. A reflow won't magically fix it. Sad that the misconception still runs free in 2024, more than a decade and a half after Nvidia bumpgate…

https://www.badcaps.net/forum/troubl...es#post1459061



https://www.badcaps.net/forum/troubl...vidia-bumpgate

Thank you. In my case this is a "contact issue". I have wrote this. Also, my card has an AMD gpu chip. In the other hand, I have another laptop with another problematic graphics card. I have bought it as used and I believe the buyer was know it has a faulty GPU (8600M GS). Just like what DynaxSC mentioned here. At the end, I'm heating that card approx in once every 3-4 months for 1-2 years. And I have another laptop which is also has another display issue. It's gpu is shorted and that is completely dead. I don't think to heat that. Neither in a BGA machine nor in an owen.

Thank you again for those good articles and for your time. Regards

[piernov]

ATi/AMD GPUs also fail a lot, very common in the HD 4000-HD 7000 generations but older ones and newer ones do fail as well…

If there is really an issue with the contact between the GPU IC and the mainboard PCB, for example if it happened after a drop or due to excessive PCB flexing, then it'd need a reball, and more often than not you'll find damaged pads after pulling the BGA IC that will need to be fixed.

For Nvidia stuff of the bumpgate era, of course any graphics card/GPU you find on eBay/Aliexpress that is not a fixed revision (with white underfill) will already be dead.

[Kemer]

Hm, I get that. It seems I'm not so lucky with GPUs, laptops, etc. Let me ask you something I don't understand. As far as I know, the contact balls are made of lead-free or less leaded (not sure) materials. And these materials should not melt at 200 degrees C and lower. So what's going on with the 200 degrees oven bake GPU solution? Thank you again.