Gold plating came off of CPU contacts.

[N3rdR4ge]

I noticed one and a half of the contacts on my 4790k had turned grey when I was cleaning my machine. I thought it might be corrosion. I lightly cleaned them and realized the contact is still fine, but the gold plating is gone. Should I be concerned about this? The machine works fine, but I'm more concerned about lifespan and/or reliability without the gold plating.

 

[Ubrales]

The socket pins and the CPU pads are gold plated in order to reduce or eliminate galvanic corrosion that will lead to contact failure. When the plating is gone galvanic corrosion will accelerate over time. Just continue using the computer as long as it works.

 

[SoNic67]

The contacts have a limited number of insertions (guaranteed 20). I don't know what you are "cleaning" by removing the CPU from the socket... See below the data for the socket (the part on the motherboard).

http://www.intel.it/content/dam/www/public/us/en/documents/guides/4th-gen-core-lga1150-socket-guide.pdf

The socket must withstand 20 cycles of processor insertion and removal. The maximum chain contact resistance from Table 6 on page 26 must be met when mated in the 1st and 20th cycles.

I think that the actual CPU contacts are limited even lower.

 

[N3rdR4ge]

@Ubrales i figured it may be more likely to corrode. i'm curious what would have caused the contacts to turn gray like that. I called intel yesterday and the rep said not to worry about it if it's working fine. warranty claim is not possible for my chip now, unfortunately.

@SoNic67 i pulled the heatsink off to dust it and reapplied thermal paste. i removed the processor to clean the thermal paste off thoroughly. also I cleaned the chip only this one time in a year and a half, so 1 insertion in 1.5 years = 15 insertions in 22.5 years. theres no way I will have the chip and socket that long. taking the chip off has nothing to do with the contacts being gray though. it wasnt even the point of contact on the contact, it was the entire contact if you understand what i mean.

 

[Ubrales]

Grey means that the gold plating (gold flash actually) was missed in certain areas This can happen when the de-greasing (cleaning ) was inadequate prior to immersion in the gold bath. These uncleaned areas will not gold plate and will oxidize. The oxidization (grey) is what you are seeing. There is no way around this issue at the present time. Just continue to use the computer.

 

[Ubrales]

The stages are Copper ---> Silver ---> Gold. If the gold is missed in spots the silver will tarnish (oxidize) and turn grey to silver oxide. This silver oxide is just as good as silver as far as electrical conductivity is concerned. (Not as good as gold, but not too bad either).

(In electrical contacts where arcing occurs, the silver will turn black to silver oxide. This silver oxide should not be cleaned off).

 

[N3rdR4ge]

thamks Ubrales. good info. i lightly cleaned off the gray and exposed the silver contact. computer is working great for now. i think i'll probably upgrade before i'll need to worry about oxidization becoming an issue.

I know of the two affected contacts, the one with half the plating missing is a VSS and the one with the full plating missing is SA_DQ9. I know VSS can possibly be redundant, but would you happen to know what SA_DQ9 is? I could not fine any info on this.

 

[Ubrales]

thamks Ubrales. good info. i lightly cleaned off the gray and exposed the silver contact. computer is working great for now. i think i'll probably upgrade before i'll need to worry about oxidization becoming an issue.

I know of the two affected contacts, the one with half the plating missing is a VSS and the one with the full plating missing is SA_DQ9. I know VSS can possibly be redundant, but would you happen to know what SA_DQ9 is? I could not fine any info on this.

No, I don't know what that is. Some contacts are set aside for future use.

Even if the silver oxidizes, the oxide of silver conducts electricity just as good as silver; so, no problems there.

 

[N3rdR4ge]

cool, thanks again