Author Topic: GTX 780 missing capacitors  (Read 365 times)

0 Members and 1 Guest are viewing this topic.

Offline didi79

  • Contributor
  • Posts: 14
  • Country: be
GTX 780 missing capacitors
« on: May 05, 2021, 04:40:23 pm »
Hi. I'm new to this forum.

I have an old GTX 780 that's missing a few capacitors on the PCIE lanes. Obviously causing the GPU from being detected.
I don't have a capacitance meter. Does anyone have an idea what type they are or what values they may be ?
 

Offline dc101

  • Regular Contributor
  • *
  • Posts: 210
  • Country: us
Re: GTX 780 missing capacitors
« Reply #1 on: May 05, 2021, 05:09:39 pm »
Can you post a picture of the section of board missing the caps? Also who makes your video card?

You could try doing some google searching for the capacitor number (CXXX) and the name of your card. There's been a few prior threads on this forum regarding video cards.
 

Offline wraper

  • Supporter
  • ****
  • Posts: 13192
  • Country: lv
Re: GTX 780 missing capacitors
« Reply #2 on: May 05, 2021, 05:16:33 pm »
Usually they are 220nF, value is not critical.
 

Offline didi79

  • Contributor
  • Posts: 14
  • Country: be
Re: GTX 780 missing capacitors
« Reply #3 on: May 05, 2021, 06:06:44 pm »
Wow fast response  :-+

Can't really see a brand, it's pretty much the reference design.

You can see the missing caps (well, you can't see, because they are missing...) near the screw with the sticker on.




 

Offline mariush

  • Super Contributor
  • ***
  • Posts: 4080
  • Country: ro
  • .
Re: GTX 780 missing capacitors
« Reply #4 on: May 05, 2021, 06:33:27 pm »
Should have the same value as the ones above  (the same values used on each pci-e lane)
So it would be enough to desolder a pair from above, measure capacitance with a decent multimeter and solder capacitors of equivalent capacitance.

Size is small .. probably less than 0402 but you could bodge bigger sizes with a bit of soldering skill and patience. 



 

Offline didi79

  • Contributor
  • Posts: 14
  • Country: be
Re: GTX 780 missing capacitors
« Reply #5 on: May 05, 2021, 07:37:00 pm »
Ok thank you.
I better invest in a capacitance tester if I want to do more repairs like this ;-)
 

Offline didi79

  • Contributor
  • Posts: 14
  • Country: be
Re: GTX 780 missing capacitors
« Reply #6 on: May 08, 2021, 01:17:41 pm »
Could not wait for delivery of the capacitance tester... So I took some SMD caps from a donor card that looked very similar.

Card is detected correctly now and I've been stresstesting it for a few hours now. Seems rock solid.

I guess most cards will indeed use similar caps there, since they all serve the same purpose (pcie lanes).

Thanks again
 
The following users thanked this post: dc101

Offline dc101

  • Regular Contributor
  • *
  • Posts: 210
  • Country: us
Re: GTX 780 missing capacitors
« Reply #7 on: May 11, 2021, 03:07:03 am »
Glad you were able to fix your card! I guess it makes sense that they are probably all the same, since they seem to exist for pcie signal conditioning which I would assume is somewhat universal across pcie cards. Probably they are more critical in higher performance, higher speed pcie cards.
 

Offline wraper

  • Supporter
  • ****
  • Posts: 13192
  • Country: lv
Re: GTX 780 missing capacitors
« Reply #8 on: May 11, 2021, 09:31:00 am »
Glad you were able to fix your card! I guess it makes sense that they are probably all the same, since they seem to exist for pcie signal conditioning which I would assume is somewhat universal across pcie cards. Probably they are more critical in higher performance, higher speed pcie cards.
It's not for signal conditioning but for AC coupling. Considering PCI-E high operation frequency, basically any MLCC cap will work unless capacitance is too small.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf