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Would someone be able to tell me if Intel/AMD publishes a data-sheet (or other documentation) that explains the role (or purpose) of every SMC (Surface Mounted Cap) which connects to the die ? I've added a picture of a delided i7-4790 Intel desktop CPU depicting surface mounted capacitors (or decoupling capcitors).

enter image description here

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    \$\begingroup\$ The capacitors are hooked up to the CPU die, not the pins on the package. The package might also (eventually) connect to some of the same CPU pins, but that misses the point. The capacitors bypass those pins, providing a more stable voltage to the die. \$\endgroup\$ Commented Feb 22, 2022 at 2:48
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    \$\begingroup\$ Also the blown up component in that image looks to me like one of the in-package inductors, not a capacitor, although its hard to tell from the image. Some scraping might give you an idea where that fire began. \$\endgroup\$ Commented Feb 22, 2022 at 2:51

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Intel has released various papers explaining the purpose the circuit you are looking at. The 16 in-package inductors and 16 groups of capacitors form a 16 phase Buck converter, or as Intel calls it a FIVR:

FIVR

More detail: https://www.psma.com/sites/default/files/uploads/tech-forums-packaging/presentations/is87-package-and-platform-view-intel%E2%80%99s-fully-integrated-coltage-regulator.pdf

Much more detail: https://xdevs.com/doc/_PC_HW/Intel_FIVR_lambert2016.pdf

From the picture you have clearly lost one of those 16 phases, but the image quality is too poor to say more for certain. My guess is you lost the inductor to a short, but you'd have to investigate that more carefully.

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Note: this answer assumes that that's a solder blob from the delidding process, not a fire from an in-package inductor. Since you didn't say, I'm not sure which it is.

Unfortunately, those details are not published.

These are almost certainly all decoupling capacitors, used to provide a small energy reservoir close to the silicon for high frequency currents.

You might be able to salvage this by carefully wicking off that blob of solder, then even more carefully removing each of the damaged parts. Use kapton tape to cover up the undamaged areas, then heat-soak the board by blowing hot air at it from a distance, moving in circles. Keep the airflow rate low. Then go in and use braid and a soldering iron to wick up that massive blob, so you can clean up with alcohol and get a good look at the damage underneath. Hopefully you've not shorted anything.

You'll need to remove any damaged or misplaced caps. With them removed, the decoupling won't be as good, so you might not get a decent overclock, but it should remain stable as long as you don't short anything or remove too many caps.

If you really want to replace the caps, very carefully desolder a nearby part of the same size and measure it with a capacitance meter. You can then try replacing the empty pads with caps of the same type. You should be able to use almost any voltage rating of capacitor (e.g. 6V) since the onboard rails being decoupled are going to be a couple of volts at most. The replacement job is risky, though, since if you short something you could kill the CPU for good. I'd generally recommend trying the CPU without the caps first, though, because an attempted repair is a high risk operation.

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