Radeon 9800xt help please

[PCBONEZ]

Re: Radeon 9800xt help please

Hi they are a massive company , unlikely to supply me 2 caps.
any alternative small company in UK
will I get the mounting discs with them?

They come assembled.
.
The manufacturer only sells wholesale.
.
The major Retail outlets on your side of the pond are RS Components and Farnell.
On this side it's Mouser, Digikey, and Newark ONE.
.
For ESR you want the same or less.
Ideally for Ripple you want the same or more.
- ESR is the more important of the two but using caps that are not rated for enough Ripple can result in overheated caps.
-
I would never advise going all the way from 5440mA to 850mA without looking at the circuit.
That cap might be on the output of a noisy POL [Point of Load] regulator and actually need most of that Ripple Rating.
POL regulators on video cards are not the least bit unusual.
.
.
As I mentioned before, in a real pinch you can retro-fit a radial.
It works, it's just not ideal or real 'pretty'.

Some people have actually reworked the plastic base from a dead SMD to make a radial fit into it.
That's a lot of messing around but it can at least work.
.

[PCBONEZ]

Re: Radeon 9800xt help please

http://uk.rs-online.com/web/p/aluminium/7149442/

[PCBONEZ]

Re: Radeon 9800xt help please

https://www.badcaps.net/forum/showthread.php?t=17398

[bwizz]

Re: Radeon 9800xt help please

Thanks , the spec is over my head but I get the gist , I notice that they have the monting base disc which I was puzzled about . I have sent a UK company a mail re min quantity . so I will report back . thanks great forum !
Brian Cornwall: UK

[PCBONEZ]

Re: Radeon 9800xt help please

These caps are filter caps.
Their job is to send Ripple Currents produced by transistors switching on-off to ground while not grounding the DC voltage.
The Ripple Current is usually right around 100kHz. [Maybe 50-200 kHz.]
.
ESR is the 'resistance' [for 100kHz] through the cap to ground.
More ESR means less Ripple gets removed and the DC will have more Ripple 'noise' in it.
IC chips don't work well with noise in their power.
.
The Ripple Current rating is how much 100kHz they can pass without overheating internally.
It's much like the amps rating of a wire but it's at 100kHz.
.
.
Some caps handle Ripple in the power rails from the main PSU but others are for transistors [MOSFETS or whatever] used as voltage regulators that are mounted locally near the device they regulate the power to. [POL = Point of Load]
POL regulators are common on video cards.
.

[bwizz]

Re: Radeon 9800xt help please

Thanks, its nice to have a background idea of how conponents work.

[bwizz]

Re: Radeon 9800xt help please

I got 4 from e bay USA $7 inc The suplliers tell me the number on top of the cap is only a date code?

[PCBONEZ]

Re: Radeon 9800xt help please

I got 4 from e bay USA $7 inc The suplliers tell me the number on top of the cap is only a date code?

4 what? - I lost track after a month w/no posts.
Depends on what they are.
Being -only- a date code would be odd.
If you find caps with -only- a date code they are crap.
Have a pic?
.

[bwizz]

Re: Radeon 9800xt help please

I had nothing to post as i had no caps! my caps have on thr 330 1200
4
The ones i have ordered have a diiferent number ie 509
1200
4
Seems legit but I am a sceptic

Thanks for your interest

[bwizz]

Re: Radeon 9800xt help please

I finally got the caps from e bay USA $7 delivered . bugger to solder in but card now works fine , I just need to sort the fan , they are not much on e bay UK
worth the effort methinks !