ATI video card capacitor

[zizo]

Hello everyone! I had a problem with my video card. It's an ATI X800XT AIW and I accidentally broke one of the capacitors. The pins are too short to solder them again, and I'm looking for a same capacitor to replace it.

Here is a picture.

so the capacitor seems to be a chemi-con and on the top it has

A 107 (?)
680( micro F?)
4v

printed on it. The case size according to chemicon catalog is J80, so I found this capacitor. APXH4R0ARA681MJ80G Except, I'm not sure if it has the same ESR.

So can anyone help if this is the right capacitor for me or not.

cap

Thank you in advance.

[zizo]

Re: ATI video card capacitor

I also found this one
APXA4R0ARA681MJ80G

which has a max ESR of 12.

[arneson]

Re: ATI video card capacitor

Look at the pads carefully, I also broke one of those yesterday.
The support for the cap is only as strong as the lands under it.

[zizo]

Re: ATI video card capacitor

all the pads look the same. I just don't know which ESR I should get. By the way, what is ESR?

[willawake]

Re: ATI video card capacitor

those polymer capacitors can come in two types. the first is surface mount which is also called chip type. they have a black plastic base under the silver cap.

the other type is the normal radial with leads that go through holes in the board. they do not have a black base

on some graphics cards the position to place the cap is configured to allow either surface mount or radial. this is not always the case though.

i did not understand what happened to your cap. was it a surface mount and you broke the cap off the base and then soldered the cap without the base back on to the board. i think this is what happened

what is esr then? well it is Equivalent Series Resistance it determines the maximum rate of current flowing in and out of the capacitor. it is very important to have a low value in motherboards and graphics cards where the current draw will vary quickly and by large amounts.

when looking at capacitor datasheets the best caps for our purposes have the lowest esr and the highest max ripple.

since the text on the capacitor starts with an A then your capacitor is chemicon PXA series if it is a surface mount or PSA series if it is a radial cap. it must be a surface mount PXA because PSA does not come in 4v 680uf.

so we have

PXA 4v 680uf - esr 20, ripple 4130
anything similar or better to that cap will be very nice.

so from mouser we see
PXH 4v 680uf - esr 22 (actually chemicon quote it as 25), ripple 3700

the case size is also a J80 which is the same. the specs are inferior to the PXA but not so much to cause problems, so it would be fine to use that. actually i am not so familiar with smt components and maybe the J80 is a chemicon specific size code.

if the cap position had holes for radial lead you could go with the PSA 4v 820 which is ESR 6, ripple 5860. an awesome cap. i have used rubycon mcz on graphics cards, they are fine also.

what is the heatsink on the graphics card?

[arneson]

Re: ATI video card capacitor

This link is real simple http://xtronics.com/reference/esr.htm
In my case, on a radar slave control board, the cap was fine, the lands broke.

[zizo]

Re: ATI video card capacitor

the heatsink was an ATI silencer4, which didn't fit my aiw card well!

alright tnx a lot. So I should order one of these two! I ordered PXH yesterday. I try to add PXA to my order. Yes the cap had a plastic base but since the pins were too short I had to remove to solder it for now so I can play my games.

[zizo]

Re: ATI video card capacitor

so what exactly happens if I use a capacitor with higher capacitance or lower ESR?

[Dan_2gngCrew]

Re: ATI video card capacitor

Hello,
I have the same problem as zizo. I accidentally broke off a capacitor. Mine also seems to be a chemi-con cap. It looks almost identical except for a red strip instead of the blue one pictured above.

The numbers on it read as follows:

361 (to the left there is what appears to be an F with a line on the top and bottom)
181
16V

I gathered that it was a 181 uF, and of course 16V. Here is what I have found on my own.

http://www.mouser.com/index.cfm?hand..._pcodeid=66106

Can anyone verify if this is the right cap? If not, maybe, point me in the right direction!!

Oh yeah, the card is a ATI Radeon 9800 Pro

Thanks in advance!

Dan
2gng Media