Broke my GTX 470, need help identifying replacement cap

[lukeman3000]

Long story short, I pulled a capacitor off my EVGA GTX 470 and need help finding a suitable replacement.

Here is a photobucket album of the damage. I have the capacitor pictured by itself in the first photo. It says:

c0
820
2.5Z

I'm guessing that c0 is the tolerance (+/- 0.25pf, 25% -- ??) 820 is the capacitance rating (82uf ?) and 2.5 is the voltage rating (2.5V?)

First of all, am I right with the numbers and units? I would really appreciate those numbers being explained to me, at least to the extent that I know how to find a replacement capacitor.

Furthermore, would the best thing be to simply remove the old posts that are still there, and just put a new cap in? Seems like an easy fix to me..

[mockingbird]

Re: Broke my GTX 470, need help identifying replacement cap

According to http://capacitor.web.fc2.com/, it could be either EneSol, OST, TEAPO or G-Luxon. The manufacturer is unknown.

My suggestion to you is to take any 2.5V 820uF through hole ultra-low ESR cap witht he same diameter.

Topcat carries these two:
https://www.badcaps.net/store/produc...products_id=76
https://www.badcaps.net/store/produc...products_id=77

I don't know what series "M" or "PSC" are, but he uses these for VRM re-caps so these are probably ultra-low ESR polymers.

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

Thank you. How sure are you those would work? Either of those would be a suitable replacement?

[mockingbird]

Re: Broke my GTX 470, need help identifying replacement cap

The second link says "Ultra Low ESR" (The "PSC" Capacitor). That is what you need for a GPU VRM. Should work just fine. I don't know what the first one is, Topcat just describes the series as "M", but I'll bet that it's also an ultra low ESR polymer...

If you want to be safe, go for the PSC.

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

Thank you so much for helping me and taking the time to reply.

Would you mind explaing what "VRM" and "Ultra-Low ESR" mean? Just to appease my curiosity. I have just enough knowledge to solder things, but I don't understand any electrical theory or anything like that. Haven't taken the time to learn it.

[mariushm]

Re: Broke my GTX 470, need help identifying replacement cap

VRM - VR is from "Voltage regulating" - it's the circuitry that takes 12v from the power supply and generates 1.xxx volts needed by the processor on the card.
The capacitor is for 820uF and 2.5v, 2.5v being the maximum voltage the capacitor is rated for. The capacitor acts as a sort of buffer for energy for the processor.

When you can't find capacitors rated for a specific voltage, you can generally go up in voltage, provided the capacitor will still fit in the area you have on the board. With regular electrolytic capacitors, usually caps rated for higher voltage are a bit taller but also have better technical specifications.

ESR is short for Equivalent Series Resistance : http://en.wikipedia.org/wiki/Equival...ies_resistance

Basically when current goes through a capacitor, the capacitor has a specific resistance - some electric circuits are more sensitive to the value of this resistance formed inside the capacitor, others are less sensitive.

Not all capacitor manufacturers specify this ESR value, generally it's safe to use the Impedance value instead which is listed in the datasheet.

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

Thank you sir

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

Another question -- is there a right and wrong way to install a capacitor? If so, how do you determine the correct way to put it in? Don't forget I provided some pics of the board if that would help..

[PCBONEZ]

Re: Broke my GTX 470, need help identifying replacement cap

Lelon OCRZ
http://www.lelon.com/index.php?fn=cat&id=9

[PCBONEZ]

Re: Broke my GTX 470, need help identifying replacement cap

Another question -- is there a right and wrong way to install a capacitor? If so, how do you determine the correct way to put it in? Don't forget I provided some pics of the board if that would help..

Yes there is a + and -.
-
On those the half moon of paint marks the negative lead.
On sleeved caps it's the stripe down the side.
.
On that board the white half moon marks the negative side.
- That's the normal PCB marking scheme but some brands [like Asus] that don't believe in following standards do it backwards so you should always check which way it's marked before you pull caps.
.

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

Lelon OCRZ
http://www.lelon.com/index.php?fn=cat&id=9

I already ordered this one. Should it be ok? If not where can I get the one you linked to?

[PCBONEZ]

Re: Broke my GTX 470, need help identifying replacement cap

The ESR and Ripple are fine but according to the Lelon data sheet the abbreviated marking scheme is only used on their 6.3mm diameter or less caps.
The one you ordered is 8mm diameter.
The lead spacing might also be different.
.
If you can squeeze it in it will be fine. [Or if Lelon lied and it's really an 8mm cap.]
If not you would have to look on Digikey/Mouser/Newark for a 6.3mm that will work.
[That assumes you are in the US or CA.]
.

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

Care to link me to the ideal replacement? I will see if I can cancel my order if possible..

N/m, saw the rest of your post. Thanks.

[PCBONEZ]

Re: Broke my GTX 470, need help identifying replacement cap

What country are you in?
[Please add it to your profile.]

[PCBONEZ]

Re: Broke my GTX 470, need help identifying replacement cap

How about the same exact cap?
http://www.mouser.com/ProductDetail/...laQktALg%3d%3d
Only one they have in 6.3mm

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

I'm in the USA.

Edit: I just checked that mouser link -- those bad boys are out of stock with a factory lead time of 18 weeks..

[lukeman3000]

Re: Broke my GTX 470, need help identifying replacement cap

What about either of these?

http://www.newark.com/nichicon/rs80e821mdnasqjt/capacitor-alum-elec-820uf-2-5v/dp/79R3117

http://www.newark.com/nichicon/rs80e...-5v/dp/79R3117

I don't really know what I'm looking for, but I just plugged in some of the specs from that one you posted from mouser that was out of stock. You might double-check my work though.. Would either of these work as a replacement?

If not, think you could help me find one that's available?

[mockingbird]

Re: Broke my GTX 470, need help identifying replacement cap

Good job PCBONEZ...

Lukeman3000 - look at the slkscreening on the PCB. There is space for either 6.3mm or 8mm caps. The one you ordered will fit.

[PCBONEZ]

Re: Broke my GTX 470, need help identifying replacement cap

The PCB isn't marked for 8mm in that spot.
By the data sheet the 270uF 16v in the back are 8mm and they are obviously bigger than the silk screen for the cap in question.
It might fit anyway.
Hard to tell in a photo.
-
The Lelon 820uF has a 2.5mm lead spacing.
The PSC you ordered has a 3.5mm lead spacing.
You'll need to bend at least one lead to correct for that so you don't put side pressure on the bung.
That isn't a big deal normally but the cap will sit higher.
-
I 'think' you have just barely enough room to fit an 8mm there.
It just won't be 'as pretty' when you're done.
Like I said. It's hard to tell for sure in a photo.
.

[PCBONEZ]

Re: Broke my GTX 470, need help identifying replacement cap

I don't really know what I'm looking for....

uF
- Always best to use the same.

Volts
- the same or more.
Must be the same or higher than actual circuit voltage.
The voltage on the original cap would be.

ESR [Sometimes 'Impedance' or 'Z' in data sheets]
- the same or less
Make sure it's rated at the correct frequency.
100 kHz is standard for low ESR caps.

Ripple
- the same or more
Make sure it's rated at the correct frequency.
100 kHz is standard for low ESR caps.

Size
- Physically fits.

I'm not surprised you were directed to an 8mm by mistake.
They 'look like' 8mm in the photo and the others 'look like' 10mm.
Also an 820uF in 6.3mm diameter is a bit unusual.
.

~~
So based on original cap you are looking for:
uF = 820uF
Volts = 2.5v or more
ESR = .007 ohms or less @100kHz
Ripple = 6100 mA or more @100kHz **
6.3mm diameter with a 2.5mm lead space.

** 6100mA = 6.1 amps.
~Really~ doubtful the traces on the PCB can handle that many amps and I'd think anything rated for 5000 mA or more would be fine.
~ That's a *guess* though!! - I can't see the other side.
.