It's a surface mount 180uF 16V aluminum polymer capacitor.

You'll want to get a replacement cap with the same specs, but also the same height/width (package size). Then it should be a matter of desoldering the damaged base and soldering the new one in its place.

You also want to be careful when removing the base that you don't accidently rip up the underlying pads. Hence, I would suggest desoldering instead of trying to pry it off.

Edited: Correction to the above, it is a polymer capacitor.

Excellent, thanks for the info, I think this is just the ticket?

https://www.amazon.com/Solid-Capacitor-180uF- … ps%2C110&sr=8-5

I'll be thinking of my mistake tonight, whilst I'm behind closed eyelids.

Not this one.

180uF 16V polymer due to purple marking set it apart from others.

Cheers,

Ah Polymer, got it.

Found it on mouser:

https://www.mouser.com/ProductDetail/667-16SVP180MX

does this look correct?

JayAlien wrote on 2023-02-08, 00:48:

Ah Polymer, got it. […]
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Ah Polymer, got it.

Found it on mouser:

https://www.mouser.com/ProductDetail/667-16SVP180MX

does this look correct?

That looks like it would work, but you will want to double check the package size (diameter & length) to match the one you are replacing.

Panasonic is a good brand for caps, so it should be reliable.

Thank you for the reminder, the one I linked was in fact the wrong length and diameter. I found the correct ones and got a few ordered. (Why am I unable to buy a single capacitor and that I always buy a few extra 'just in case'?)

Why does size matter?

Nexxen wrote on 2023-02-08, 02:23:

Why does size matter?

It just ensures proper fit.

In some cases size variation won't matter depending on the board / pad layout. But in my experience it's easier to just match components accordingly.

Well I got the new cap and replaced it. Continuity test with a multimeter shows good connections from the pads either side of the new cap, but still cant get the system to even power on with this card installed (System works with a Radeon 9700).
I'm not getting a continuity test across some of the other caps towards the top of the board. I think this card may be toast, or beyond my ability to repair. 🙁

Can you provide a full high resolution pic?

Of course, here it is.
Ah, I had to lower the resolution a little for the 2mb limit

EDIT - I tried this GPU in another P4 system and same behavior, a momentary pulse of all the fans but no boot. Putting the Radeon 9700 in this second system booted just fine.

Have you checked for shorts?
Maybe a dead mosfet?

By the looks of it, those 2 purple caps are on the 12V input for the vrm from the molex connector . If you have a good PSU and the video card is fine, it should boot/work without both of them. Use a multimeter and check for continuity between(without system power) the yellow molex wire (12V) and the unmarked pins of the caps(they have 2 pins one is not marked an the other is marked by the purple shape from the cap. Then check so you don't have continuity between the 2 pins of the cap, then with the multimeter set to voltage mode and system powered on check again if you have 12V between the 2 pins of the caps(be careful not to short something).

Without the 12V molex, does it output the "shutdown your pc and plug the 12V connector" (or similar message)?

I don't know about the FX5900XT, but my FX5900 Ultra does not display anything without the molex connector plugged in.

bogdanpaulb wrote on 2023-02-15, 13:41:

I don't know about the FX5900XT, but my FX5900 Ultra does not display anything without the molex connector plugged in.

I thought it could be. My Radeons do. Well, wouldn't be a funny troubleshooting job otherwise 😀

Thanks for the advice so far

>>Use a multimeter and check for continuity between(without system power) the yellow molex wire (12V) and the unmarked pins of the caps(they have 2 pins one is not marked an the other is marked by the purple shape from the cap.
I get continuity between the yellow molex and both sides of both the purple caps.

>>Then check so you don't have continuity between the 2 pins of the cap,
I do have continuity

So I have a short perhaps?

I haven't tested for 12v across the caps yet, but if I have a short not going to see a voltage across the caps....

EDIT - I have continuity between the yellow molex and both black cables. I've got a short.

EDIT 2 - I removed the cap I soldered on in case I'd created a solder bridge, and cleaned the pads. With the cap removed I still have continuity both across the empty pads and across black/yellow at the molex connector.

Post a high res pic with the area selected (front and back).

Thanks for looking, here are the images