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I have purchased an RTX 2080 which contains a scorched component. I have carefully removed it with a heat station. The card is not short and it works, but it is seen with artifacts.

As I found on the internet, I believe this is a ferrite bead or an EMI filter. I went ahead and measured the size of the component and I think it measured between 2mm x 1mm and 1.6mm x 1mm.

Do you think that not filtering of the electromagnetic interference is causing the artifacts or the problem is from another component (maybe the RAM)? Also, can I solder a ferrite bead of similar characteristics (a ferrite bead of the same size) or does it have to be the exact one to not mess with the circuit? I am not really certain on how ferrite beads and EMI components work

enter image description here

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    \$\begingroup\$ If those are ferrite beads (or resistors, or whatever they are), they do not just melt like that for no reason. There is something wrong elsewhere on the board. Ferrite beads that appear with the same numerical specs from different manufacturers are almost always actually different since the number provided is just a single point on a graph and the entire graph itself is what matters. Also current rating. Ferrite beads are rated for heat but the core saturates and they stop doing the ferrite thing at far, far below that current rating (1/10th). Wrong ferrite bead can worsen noise than no bead. \$\endgroup\$
    – DKNguyen
    Dec 18, 2021 at 18:25
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    \$\begingroup\$ As those components have melted themselves, it means they worked as fuses if there was an overcurrent situation. It depends what caused the problem. If the problem is still present, putting new ferrite beads might also melt themselves. If the problem was only momentary, such as user shorting something on the board accidentally, the problem is not present any more. In any case some sections of the board can now be unpowered, which can cause the disturbances, but it also should not be used if some sections are unpowered. \$\endgroup\$
    – Justme
    Dec 18, 2021 at 18:26
  • \$\begingroup\$ They look like EMI filter beads situated right near the power connector. Probably there is some short on the board that has led to excessive current draw. Remove the burnt beads and measure continuity from the VIN to GND. \$\endgroup\$
    – tobalt
    Dec 18, 2021 at 18:35
  • \$\begingroup\$ @Justme I have recently removed this ferrite beads from the board and the GPU is working with the same artiffacts, which makes me believe that they might work as fuses. It could be that the due to the ferrite beads being burned or not present on the board the 12V rail might not be closed therefore underpowering the board. How would you recommend me to test if the ferrite beads are the issue? I was thinking of connecting a thin copper power were the ferrite beads were once but I am not really sure how this is going to affect the GPU. \$\endgroup\$
    – Expoespa
    Dec 18, 2021 at 19:25
  • \$\begingroup\$ @tobalt I have 2 questions. The fist one you can see above this comment. The other question is what and where is the VIN on a GPU. \$\endgroup\$
    – Expoespa
    Dec 18, 2021 at 19:28

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Those ferrite beads (FBxx in most schematics) are most likely used to filter power for an analog circuit. They act as transient absorbers by varying the resistance to high frequencies. Without them, digital noise is most likely getting into an analog circuit where it shouldn't (DAC for example).

Since you don't have the schematics or part numbers, you could start with 1K @ 100MHz devices and work your way down until the artifacts diminish. They really are low cost critters, so buy several ranges in one shop. Just match to your PCB pad size. Looks to be an 0603 by comparison to the 0.1" connector pins above.

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  • \$\begingroup\$ I think that the solution you just gave me may work for me. \$\endgroup\$
    – Expoespa
    Dec 19, 2021 at 0:46
  • \$\begingroup\$ I have been looking for ferrite beads but I dont know which ones I need to get. Can u please tell me what ranges and characteristics I need to look for? Aso what dpo u mean with 1k and with 100Mhz?? Thank you a lot \$\endgroup\$
    – Expoespa
    Dec 19, 2021 at 1:02
  • \$\begingroup\$ Without a proper schematic, its just a guessing game. First confirm your PCB size for those parts, then order some with the impedance at frequency specified in a range of 1kohms down to 500ohms, rated at 100MHz. \$\endgroup\$ Dec 19, 2021 at 1:10
  • \$\begingroup\$ We just discovered that our GPU model is v18044 if, by any chance, you know of any place to look for .fz and .cad files. Here is my email: luisyluiscanada15@gmail.com \$\endgroup\$
    – Expoespa
    Dec 19, 2021 at 3:23
  • \$\begingroup\$ I really appreciate your help :) (L) \$\endgroup\$
    – Expoespa
    Dec 19, 2021 at 3:24

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