I baked my GTX 480 a while back successful, but after two months i got another black screen. So i baked it again. and it worked great, for a month. So i baked it again, and it worked for another 2 months. Does anyone has a tip to fix it permanently?
At best, it can be used to buy yourself a little bit of extra time while you aim to replace - shy of investing some decent money (ie more than a 480 is worth) into it, the card will fail again, eventually - and you'd be better off buying a new card.
If you want to bake it you need to apply a good SMT rework flux under the IC , and using a normal oven is far from ideal as it takes too long to heat up the PCB ( 250C )which can damage other components. It really needs to be done in a proper reflow oven set to a proper reflow profile.
baking might only possibly do something if the fault is something that baking can fix, most faults are not of that type. Baking could easily make things worse.
Does your heat sink screw on and/or can it be replaced with one that can screw on? Maybe you could use a screw-on heat sink to put a little extra pressure on the top and see if that resolves the issue.
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I think this post covers most of what you are looking for. There are two theories of what causes this issue. If the card needs a solder re-flow, then you really need to do it with heat gun/heating station. If it is actually a "bump" on the substrate, then there is no real fix other than a new gpu or new chip.
I've successfully baked a card before. It's still working to this day. I did it because my card is old and out of warranty. In your case, why didn't just get an RMA for it from the manufacturer? It should still be under warranty?
GTX480's launched in 2010. No warranty likely to still be available there.
I assume you've mistaken for an RX480 from AMD?
Sorry about that. Yes, I was thinking AMD, Not Nvidia.
1: 480's were very power hungry cards. Maybe try using a different cable from the PSU? (you might be getting dirty power)
2: I'm sure you did but I'll ask anyway, You did strip the card naked from it's fan shroud before you baked it?