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Comment on Resistor/Capacitor broke off, anyone knows if it matters?

Are those near a connector (maybe on the other side?)

Could be a bunch of ESD protection diodes which only come in to play if you wear socks on carpet and touch the connector terminals.

Can you provide the numbers listed on the parts? Usually just 3 numbers/letters.

Also, looking at the circuit traces, does it look like all three terminals are connected? Is one connected to the ground plane? (The copper that covers most of the board surface around the circuit traces).

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dave@feddit.uk ⁨1⁩ ⁨week⁩ ago
From the TI briefing note:

Paralleling power metal-oxide semiconductor field-effect transistors (MOSFETs) is a common wayto reduce conduction losses and spread power dissipation over multiple devices to limit the maximum junction temperature.

It would also provide redundancy in case of a failure—if you had only one, and it failed (or was scraped off by an over-enthusiastic GPU installation), you would probably not be going to space today.

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- great_7562@ani.social ⁨1⁩ ⁨week⁩ ago
  So I guess, what this means is having one scrapped off or failing isn’t a big issue (because of built-in redundancy accounting exactly for that)?
  
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  - dave@feddit.uk ⁨1⁩ ⁨week⁩ ago
    My gut feeling is they didn’t put 20 there in case you scraped one off. But likely the others will have enough leeway to cover for it. If the power rail gets stressed enough, it might well fail sooner than it would have.
    
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    ch00f@lemmy.world ⁨1⁩ ⁨week⁩ ago
    My other running theory is that (due to relative proximity to audio chip), they’re muting FETs for muting audio channels when connecting headphones/speakers to prevent speaker pop.
    
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- ch00f@lemmy.world ⁨1⁩ ⁨week⁩ ago
  Can you link that note?
  
  I think that’s usually the method in high power applications where heat dissipation is paramount. Each of these diodes is only rated for 210mA of drain current. From a BOM cost perspective, it’d be much cheaper to just buy one 5A FET rather than parallelizing a bunch of 0.21A FETs. That 5A FET would be in a package that could handle whatever heat it generates.
  
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  - dave@feddit.uk ⁨1⁩ ⁨week⁩ ago
    You’re probably right—I searched for ‘20 mosfets in parallel’ or something like that and it came up near the top. But I didn’t read the whole thing.
    
    I guess there’s got to be some reason for using so many though?
    
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great_7562@ani.social ⁨1⁩ ⁨week⁩ ago
It’s like well, here I guess:

i.postimg.cc/XJNcnppT/modelblock-gaming-pd.png

You might be able to find a better resolution image of the board if you look, on them, it is written K72 then vertically smaller K2 (the 2 has an underline).

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- ch00f@lemmy.world ⁨1⁩ ⁨week⁩ ago
  Here’s another idea. In that image, directly below these FETs you can see the little crab logo on the chip. That’s the audio driver. It’s possible these FETs are muting FETS for the analog audio channels. Basically they hold the audio lines down while you connect/disconnect your audio devices. If the motherboard supports 9.1 audio, that’d explain why there’s 10 of them. One per channel.
  
  Like this: Image
  
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  - dave@feddit.uk ⁨1⁩ ⁨week⁩ ago
    That mb appears to have 8 channel audio on the backplane (7.1) and maybe another stereo header for the front panel headphones? That would make 10 channels in total which fits…
    
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