Broke an SMD component ..  - Page 1
Forum section: electronics / general

author: tp4tissue
author_rank: Newbie
timestamp: June 04, 2016, 05:02:38 pm
content: Hi gurus:You guys seem extreme knowledgeable on hard modding..I accidentally broke off an smd component next to my gpu die..I don't have a meter that could measure that low either. so i can't take off the one next to it and measure that.Does anyone happen to have schematics or know the value of a replacement smd cap ?This is an Nvidia 670 Gigabyte windforce.. Image belowSince the capacitance is so low at these sizes 0402.., do ya'll think maybe I could just get Wing-It.. hahahaha and just buy a random cap

author: jpanhalt
author_rank: Super Contributor
timestamp: June 04, 2016, 05:47:14 pm
content: In the 402 size of ceramic capacitors, the range in values is from 25 uF to 0.1 pF. I don't think 25 uF is particularly low. Common values will be 0.01 to 1 uF. Do you have the capacitor you inadvertently broke from the board? Are you sure it belongs ther or at the other open space on the board?Given that such circuits are often quite duplicative or symmetrical, your best bet is to measure the one you released from its bindings. Failing that, I would remove one of the others and measure it. Be sure to replace both.Now, about that open space at the bottom...was it there when you started messing with the board?John

author: Tinkerer
author_rank: Frequent Contributor
timestamp: June 04, 2016, 05:53:28 pm
content: Once had a cap knocked off a graphics card. Was quite a bit larger though, aluminum one I think. Resulted in a crash happening every so often but not too much more. I ended up replacing the card not that long after anyway.After a quick search, seems datasheets on that chip is lacking so we cant be 100% sure what those caps are doing. Although I do notice at least one cap which was not placed so either that spot wasnt utilized or the caps simply help and arnt essential. Someone will have to look a bit more than I did.

author: tp4tissue
author_rank: Newbie
timestamp: June 04, 2016, 06:13:11 pm
content: Yes, I am sure that I nicked it while I was cleaning the card.. I've already compared it with other photos of this chip.. That space is definitely occupied..I'm not actually sure if it's a capacitor or a resistor, but it's most likely a capacitor..I can't take off the ones next to it to measure, because I do not have a meter that will measure this low, and the ones that do cost more than this card..Rock, meet hard spot... hahahaha...

author: Monkeh
author_rank: Super Contributor
timestamp: June 04, 2016, 06:29:21 pm
content: The card will probably work perfectly fine without it.You will never, ever find a datasheet which tells you anything about that part, and you'll most likely never find anyone who knows what value it is. Even the card manufacturer has no clue, they buy the entire chip complete, they don't populate those.

author: amyk
author_rank: Super Contributor
timestamp: June 05, 2016, 03:36:36 pm
content: ...unless you find someone here who happens to work for nVidia, knows what that part should be, and isn't afraid to tell you.

author: XOIIO
author_rank: Super Contributor
timestamp: June 05, 2016, 04:14:29 pm
content: Just email nvidia and ask for the full schematic, I'm sure they will gladly send it out :p

author: Monkeh
author_rank: Super Contributor
timestamp: June 05, 2016, 05:17:02 pm
content: Quote from: amyk on June 05, 2016, 03:36:36 pmYeah, if you can find one of the five people who has any idea..

author: georges80
author_rank: Frequent Contributor
timestamp: June 05, 2016, 06:05:50 pm
content: It'll just be a bypass cap. If you ohm the pads to nearby caps it's likely in parallel with them.I would just run it as is. If totally anal, just solder a 0.1uF cap in place or a 0.1uF in parallel with a 1uF if you want to cover the bases.cheers,george.

author: ovnr
author_rank: Frequent Contributor
timestamp: June 05, 2016, 09:07:29 pm
content: Also, if you do replace it (you really should be fine without it!), be sure to solder it on haphazardly, so that it rises above the top of the GPU die and prevents your cooler from mounting correctly. /s

author: tp4tissue
author_rank: Newbie
timestamp: June 05, 2016, 09:55:21 pm
content: So, what is the Most likely in this scenario.. 0.1uF or 1uF.. also, what voltage rating.. I know this GPU chip runs 1.175v during Load.

author: ovnr
author_rank: Frequent Contributor
timestamp: June 06, 2016, 12:11:08 am
content: If I had to guess, 0.01 uF. But honestly, unless you're experienced with soldering 0402s, it's safer to just re-assemble the card and check if it works - which it probably will! - than to mess around with soldering on a new cap.

author: tp4tissue
author_rank: Newbie
timestamp: June 06, 2016, 12:08:28 pm
content: Quote from: ovnr on June 06, 2016, 12:11:08 ambut, what could go wrong.. ? I mean.. is there something specific about 0402 that's more dangerous to work with?

author: ovnr
author_rank: Frequent Contributor
timestamp: June 06, 2016, 02:10:15 pm
content: No. But the substrate to which the caps are soldered is not invincible, and faffing around soldering on random caps isriskierthan just checking if the card is fine as-is.Seriously: It. Is. Fine. And unless you can demonstrate the opposite, that's the end of that.