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tl;dr: how to procure a SMD replacement if all i know is the 3R3 marking and sizes (square 6.5mm sides, 2.9mm tall), with no extra information on thermal, etc.

One component on my motherboard fried to the point i can barely read the top markings. It's a large SMD one with only two large pads, so i believe I can replace it with a hand soldering iron.

I have zero experience with SMD stuff and can't really ID it. Looks like a resistor from the rest of the circuitry. 3R3 = 3.3Ω? That is a stock photo and shows top markings 3R3 348 CXD, On my same revision board, both of those are labeled 3R3 518 R06 so I am guessing the last 6 digits are just factory/serial garbage.

That region of the motherboard is clearly the power regulator from the 12-19V input plug. So i guess don't have to worry too much about anything else other than correct resistence value and Thermal capacity i guess, right?

AM1h-ITX motherboard with burned component marked in green

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    \$\begingroup\$ Given that it is in the middle of a switching powersupply, it might well be an inductor rather than a resistor. \$\endgroup\$
    – JRE
    Jul 16, 2020 at 20:41
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    \$\begingroup\$ It is most likely an SMD inductor from the looks of its package. \$\endgroup\$ Jul 16, 2020 at 20:42
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    \$\begingroup\$ Keep in mind that it's unlikely to be the only part that is "fried". \$\endgroup\$ Jul 16, 2020 at 20:53
  • \$\begingroup\$ @SpehroPefhany i know, but there's no option to buy a new one today. We live in an age that the factory-included CRC battery outlast the life of the product. Going to give it a try before replacing CPU for lack of board options. \$\endgroup\$
    – gcb
    Jul 16, 2020 at 21:48

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It is most likely an 3.3uH SMD inductor. Something like the one shown here: https://www.sunrom.com/p/33uh-3r3-10a-smd-aspi-0630lr-3r3-inductor

It is indeed easy to get confused and believe this is a resistor when the marking includes the “R”.

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  • \$\begingroup\$ Thanks. I see the same 3R3 marking used from components with a wide range of other attributes besides 3.3uH. I know i need shileding just from the looks. but there's also max i from 1A to 30A, and DC r from kΩ to 10s of MΩ. Any way to figure those out from the original markings? \$\endgroup\$
    – gcb
    Jul 16, 2020 at 21:43
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    \$\begingroup\$ guessing this is a good replacement based on the ranges of the nearby components: mouser.com/ProductDetail/673-PA5005.332NLT \$\endgroup\$
    – gcb
    Jul 16, 2020 at 22:27

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