8800GTX PCIe connector Repair

[JaD]

Hello everyone,
an unlucky accident (unvolountary system powerup with the unmounted board touching a PCI connector) caused two of my 8800GTX's pins to burn out. As you can see in the following closeup

http://www.setiron.com/varie/8800_pcie.jpg

the sixth pin is completely gone and just a small glitch is left from the seventh.
From what i can read here http://pinouts.ru/Slots/pci_express_pinout.shtml those should be SMB data signal and a ground pin respectively (it's the "B" side, front of the card, where the GPU is placed).
For the latter, there is obviously no problem replacing it (soldering an external wire to what remains from it should make the job), but regarding the SMBus pin...i don't see any way to connect it. As i have previously stated (and as you can see from the picture) there is nothing left from it and i can't understand how it was originally connected (to an internal pcb layer maybe?).
Being the SMB a relatively low frequency signal, an external wire could be a viable option aswell (connected directly from the vga to the MoBo's PCIe back soldering point) but i have absolutely no idea of where to pick an alternative SMBus data signal.

Any hints?

Thank you in advance and sorry for any grammar incongruence, teaching English wasn't considered of much importance back at the school i attended :\

[cirthix]

ouch, that's a tough one to repair.

your only real option is to find alternative points on the card and attach those to makeshift pads. Maybe you could epoxy or superglue a coulpe of copper foil pices, clamping down as the adhesive cures, cleaning the pad, and then attaching it to the smbus.

The easiest place you may be able to find the smbus pins would be on the voltage regulator controller chips and/or on the fan control.

good luck fixing it though.

smbus runs at 10-100khz, so it's very slow.



have you verified that the motherboard still works? with that much damage to pins on the smbus, i'd expect that to be fried too.

[STEvil]

the ground pin could be looped to another grounding location probably, if it is even needed.

The smbus one would probably be best fixed by gluing down a copper sheet (as cirthix said) then cutting it to size as needed. Good idea to pre-solder a wire to it maybe then see if you can trace where the trace goes to on the pcb of the videocard and run a wire to there.

You could glue a large peice of copper sheet and cut it in two then run the one to ground (top light green trace seen I would assume) and do as described with the smbus one as well if you dont want to run the ground to another ground.

Test the pci-e slot to see if the ground pin where it goes to is a separate ground plane from the other ground pins of the pci-e connector.

[s0lid]

That's tricky to fix :P
I can buy that btw :) sry i know than this is against XS forum rules!

[cirthix]

the ground pin could be looped to another grounding location probably, if it is even needed.

The smbus one would probably be best fixed by gluing down a copper sheet (as cirthix said) then cutting it to size as needed. Good idea to pre-solder a wire to it maybe then see if you can trace where the trace goes to on the pcb of the videocard and run a wire to there.

You could glue a large peice of copper sheet and cut it in two then run the one to ground (top light green trace seen I would assume) and do as described with the smbus one as well if you dont want to run the ground to another ground.

Test the pci-e slot to see if the ground pin where it goes to is a separate ground plane from the other ground pins of the pci-e connector.

i can almost guarantee that the ground pin isnt needed

smbus has no special ground lines, it's reference ground should be the same as every other ground on the board. he probably only needs to fix the smbus data pin.

[JaD]

Ok so that's it...i checked the PWM regulator's sheet (http://208.109.51.75/PrimarionMain/Documents/PDB-3540.pdf), there is no pinout but it should to be the same of 3535's (http://208.109.51.75/PrimarionMain/Documents/PDB-3535.pdf), considering that it's looking at it that people figured out where to solder to Vmod the card (http://www.xtremesystems.org/forums/showthread.php?t=123046&page=2 post #33)
If i'm not wrong, PIN44 should be the one carrying SMBus data signal, right?

http://www.setiron.com/varie/3540.jpg

From what i can see, PIN44 goes up to the red dot and that's where i'll have to solder. Can you guys confirm that?

[cirthix]

that looks right. it might be easier to solder to the resistor that's connected to it than the pad.

[bikerdude]

Hi there

As you can see from my pic its only the outer pin (on the r/h side)is the only one that actually has a connection!!! The middle 2 pins dont appear to connect to anything.. I reckon you could get away with either gluing a small sliver of tin foil in place and then using conductive paint to make the connection - or just using conductive paint period...!!!

biker

http://img292.imageshack.us/img292/742/88gtxcntrjf7.jpg