How big of a capacitor to use in my cpu socket?

[acv159357n]

heyhello,

 

i got my hands on a free motherboard, with a missing cpu socket. now i can replace that, thats not the problem.

the problem is, that the previewous owner moved a lot of the ceramic capacitors in the middle of the (LGA1150) socket. a lot are missing alltogether aswell.

i dont have a capacity meter, how can i know what capacity capacitors i must install? i know one a bit different isn't that bad, but in what range should i be?

i am experienced with microsoldering, replacing is no problem.

 

best regards

[I-r0k]

There is a really easy answer to this: Don't. You're probably going to accidentally kill yourself. Remember there was a reason why it was free.....

[acv159357n]

2 minutes ago, I-r0k said:

There is a really easy answer to this: Don't. You're probably going to accidentally kill yourself. Remember there was a reason why it was free.....

how would i kill myself..? its not like a power supply or something. the reason the socket was taken off, is because too many pins were bend, and the other owner wanted to replace it. too bad he f*cked up.

 

really no danger by doing this. its low voltage, small capacity. if i would be opening a psu, sure. but snall SMD's like these are not a bit dangerous. maybe to swallow.

[thedabbler]

So are you just wanting to do this for fun??

[I-r0k]

2 minutes ago, acv159357n said:

how would i kill myself..? its not like a power supply or something. the reason the socket was taken off, is because too many pins were bend, and the other owner wanted to replace it. too bad he f*cked up.

 

really no danger by doing this. its low voltage, small capacity. if i would be opening a psu, sure. but snall SMD's like these are not a bit dangerous. maybe to swallow.

If you know what you are doing then you should be fine.

[acv159357n]

1 minute ago, jmoles said:

So are you just wanting to do this for fun??

yes indeed. but my goal is to succeed haha.

i'll look into a capacity meter, one that can measure such small capacities

[acv159357n]

Just now, Pangea2017 said:

Aren't these caps for the power supply? going larger should not be that bad.

If you want you could messure the rise time of the other caps and do the math to get the size or build a LC circuit.

meh, i'm talking about the very small ceramic capacitors that are inside the LAG socket. they're size 0805 (2.0x1.3mm) and dark brown.

[acv159357n]

Just now, Abyssal Radon said:

You could go online and find detailed pictures of the board to figure out what you’ll need.

thats the problem. ceramic capasitors like these small ones are not labled and undocumented by the manufacturer (MSI)

[mariushm]

Forget about it.

 

Those are ceramic capacitors and inductors used for decoupling and filtering. They're of various capacitance values and technical properties, because each one reacts differently and filters specific parts of the power going into the cpu through those pins.

 

So the ceramic capacitors may be a mix of 10nF , 47nF, 0.1uF, 1uF ... maybe even 10uF or 22uF but just the capacitance is not enough there... even though the voltages a cpu sees are less than 2-3v, the manufacturer will use ceramics from specific series for their mechanical and electrical properties .. for example they may use 10nF rated for 10v because it's the only one in 0205 footprint, and they may use 47nF in 0402 footprint because it had to be rated for 16v at least, to reach some technical specs.

 

There is some leeway but basically those capacitors are important for cpu stability, without the proper ones you could get memory errors, errors when transferring data between cpu and pci-e slots (so you may not get cpu crashes, but could get lots of pci-e errors which could crash game or slow down game)

 

... and replacing the socket .... highly unlikely without good equipment

[aezakmi]

5 hours ago, I-r0k said:

There is a really easy answer to this: Don't. You're probably going to accidentally kill yourself. Remember there was a reason why it was free.....

yeah eating the capacitors could kill OP

 

but what are the odds anyway

[acv159357n]

17 hours ago, mariushm said:

Forget about it.

 

Those are ceramic capacitors and inductors used for decoupling and filtering. They're of various capacitance values and technical properties, because each one reacts differently and filters specific parts of the power going into the cpu through those pins.

 

So the ceramic capacitors may be a mix of 10nF , 47nF, 0.1uF, 1uF ... maybe even 10uF or 22uF but just the capacitance is not enough there... even though the voltages a cpu sees are less than 2-3v, the manufacturer will use ceramics from specific series for their mechanical and electrical properties .. for example they may use 10nF rated for 10v because it's the only one in 0205 footprint, and they may use 47nF in 0402 footprint because it had to be rated for 16v at least, to reach some technical specs.

 

There is some leeway but basically those capacitors are important for cpu stability, without the proper ones you could get memory errors, errors when transferring data between cpu and pci-e slots (so you may not get cpu crashes, but could get lots of pci-e errors which could crash game or slow down game)

 

... and replacing the socket .... highly unlikely without good equipment

Too bad about the caps.. i think you are right. I allready have the replacement socket, so i'll try to find a motherbord with just a screwed socket, and intact caps. Thanks for the reply!

[r4tch3t]

If it was me I might try anyway, those caps are there to smooth the power delivery to the cpu. Just replace them with whatever values fit. It should at work fine. It's unlikely to damage the CPU, it could just be unstable.

But then if you can find another board that's more intact it would be easier and you wouldn't waste the socket.

[Unimportant]

1 hour ago, r4tch3t said:

 Just replace them with whatever values fit. It should at work fine. It's unlikely to damage the CPU, it could just be unstable.

Real capacitors are not perfect, they have parasitic inductance (ESL) and parasitic resistance (ESR).

The ESL and C have a resonant frequency, which is the knee point in the typical "V" shape in the impedance vs. frequency curve.

Haphazardly picking random capacitor values and case styles (large factor in ESL) can cause anti-resonance peaks in the impedance curve.

 

Google "decoupling anti-resonance peak" if you're interested.