Instant diagnosis of bad video board caps?

[RonCam]

Hi, new member here! Just found out about the 'capacitor plague' and what a surprise, there is such a store of information available about it.

does the following make for an instant diagnosis of bad caps on the video board?

About once every day or two, my monitor instantly goes black, sometimes with the display driver restarting, but more often with a MS Windows blue-screen listing (among other things) the name of the display driver.

At this point, it could be a number of things, but I noticed something unusual, when I happened to be running a video at the same time:

The screen went instantly black, but the audio continued going, without distortion or loss of volume, for at least three or four seconds, until it also stopped suddenly and was replaced by a faint buzzing sound.

My reaction was, that the video card must have cut out first, followed by the motherboard.

As always, a hard reset and reboot brings everything back, perfectly (until the next time, that could be hours, or a day, later).

I'm thinking this must point to the caps on the video display card, considerably narrowing down the area where I should start looking.

Since there are lots of people here, with lots of practical experience, who have 'seen it all' -- does this sound logical, or could the problem still be anywhere?

[RonCam]

Re: Instant diagnosis of bad video board caps?

The case was opened and no signs of oozing or bulging caps on the motherboard.

The video card was removed for close examination. This is an ATI Radeon X300SE 256MB with HyperMemory, and the electrolytics here also show no signs of oozing bulging. I have a Capacitance Meter on the way through the mail, but after I saw C105, and how it was installed, I may not even need that (see attached image).

This card has a fanless heatsink, that therefore runs warmer than fan-cooled models, but note the Radeon board's unique way of avoiding overheating of the sink, by digging its edge into the electrolytic's plastic sleeve, probably getting metal-to-metal contact, and so preserving the life (of the heatsink!!) by dumping its excess thermal energy into the electrolytic's shell. A marvelous piece of engineering, indeed.

Do they make all their boards this way, or am I just lucky?

I don't think this is the 'capacitor plague' -- I suspect it's just 'heat-sink cooked capacitor'. It's rated at 1000uF 6.3v, but I'll try my Capacitor Meter on it as soon as it arrives. I suspect it's going to be down, a bit??

Advice, please: I'm sure not going to install the replacement cap in the same way. I am thinking about a Nichon brand cap, one that comes with a smaller diameter and a slightly higher shell. Good idea??

Any comments on what I'm proposing? Or, would anything be better than the original factory installation?

[mariushm]

Re: Instant diagnosis of bad video board caps?

Measure the diameter of the capacitor then lookup Panasonic FM/FR series, Nichicon HM/HN/HZ series, United Chemi Con KZE, Rubicon Z** or RX (high temperature, but select ones rated for 10-16v instead of 6.3v for better specifications)

If you find only wide caps at 6.3v you may find capacitors rated for 10-16v that are less wide but taller. Going up in voltage is OK, just don't change the capacity value.

The series I mentioned above are the kind of series that have high ripple and low impedance/esr, both important on computer parts. Not all series or capacitors can be used, just by getting same capacitance value.

Note that you won't get accurate measurement with the capacitor mounted on the board. Take it off to do measurements. Even so, capacitance could be within specs (+/- 20% but ESR could be high, due to the temperature it was subjected to)

Later edit: If you replace one, you should replace the other one as well or the ones near it if there ares several. Replace all if the brand is OST - afaik they're unreliable.

[RonCam]

Re: Instant diagnosis of bad video board caps?

... then lookup Panasonic FM/FR series, Nichicon HM/HN/HZ series, United Chemi Con KZE, Rubicon Z** or RX (high temperature ...

Thanks for the help!

Question: Of the brands you mentioned, on the badcaps home page, lefthand menu (Capacitor Kits) I don't see Panasonic or United ChemiCon KZE -- or RX. How, or where, does one order these (should one of these brands be the preferred choice, over Rubicon and Nichicon)?

You raise a good point about deterioration that wouldn't be noticed with a regular Capacitance Meter. Yes, I may as well replace all -- they're only four larger electrolytics, in total, on the Radeon board.

Another question: changing the diameter will change the distance between the leads, no? You have experience in actually doing this? I trust this will not make things 'messy' -- just spreading the leads a bit will create no mechanical problems?

[mariushm]

Re: Instant diagnosis of bad video board caps?

I don't own this website so I don't know exactly what brands are for each value, but usually they're carefully picked series of capacitors suitable for motherboards and video cards and power supplies and so on.. you can buy from the main website with confidence, they'll be good for your video card.

I believe some of the capacitors sold on the website here are the kind with very small dimensions (diameter AND height) because some tall capacitors would block CPU heatsinks if they're too tall. These capacitors are harder to find, are also more expensive because of this. Often you don't need that small diameter and height combination, as you can search for capacitors taller but smaller in diameter to get the same specifications.

The series I mentioned are more easy to find in some cases and that's important if you're not living in US as the shipping costs may be too much for you.

There are three good websites that I know of, and I've used two of these with no issues.

Digikey.com (nichicon, panasonic, united chemicon) - used, great for us, kind of expensive shipping for some countries outside us

mouser.com (didn't use, see for yourself)

farnell.com - has custom websites for various countries (like uk.farnell.com for example), shipping can be very cheap or free, has good series of Rubycon, nichicon and Panasonic are also there but not as much variety (series and values) as on digikey

Rubycon is not sold by digikey.com and that's why you won't see many people recommending it on this forum but it's a good, reliable brand. Same with Samxon - I think there's a forum member selling those.

The distance between leads doesn't change that much - some diameters have the same lead distance. The datasheets list the distance lead so you can see for yourself.

What to choose over another? Generally, you have to look up the existing specifications for the capacitors you have... ripple, impedance, diameter you can use. Then you need to pick one that has equal or higher ripple for the capacity you need and lower or equal impedance.
You can select a few and then pick whatever it's on stock or depending on your budget.

[RonCam]

One more thing -- before pulling the caps

Wow! This a great forum! Thanks, mariushm, for all the practical hints, and especially for the electronics supply references. I am in Portugal and we don't have any RadioShacks here.

Looking at the photo I posted, and how the sharp edge of the heatsink is cutting into the cap's insulating sleeve (note a little curl of plastic, near the cap's base, where the cap and sink touch), I will first try one more thing: remove the heatsink from the card and put a 45° bevel on that edge. I hope it's fairly soft aluminum.

Then an identical-size replacement cap, or anything else, will be OK.

It crossed my mind, that the problem may not be heat damage, but an intermittent electrical short between the heat sink and the cap's outer can, as the sink heats and cools. If correct, then the problem will then disappear.

If not, then order the caps, get out the iron and solder-sucker.

[Scenic]

Re: Instant diagnosis of bad video board caps?

If that's really a passive cooled (?) X300SE with hypermemory (= stealing system RAM like chipset integrated crap), i wouldn't really bother with it.

I've seen so many of these with faulty GPUs from running for years at 70+°C..

[RonCam]

Why are we doing all this??

... i wouldn't really bother with it. ... I've seen so many of these with faulty GPUs from running for years at 70+°C..

Yes, that crossed my mind, but there are other factors ... I'm dual-booting Windows 7 Professional / Windows 2000 Professional, and a new card may not have drivers for the latter.

I might add, the X300 is running with Windows 7 just fine. It includes a driver for this board, since ATI-AMD's driver support for this model goes up to Vista, only.

This I may consider, a completely new video card, once Win 7 is running and configured as well as Win 2K ... the only reason the older system is still here. So I have to run in parallel for just a bit longer.

I would be farther along with this, except the video crashes began during this transition, then I was blaming Windows 7's video driver, until I discovered it was happening with the Windows 2000 driver, as well. Then I looked to the hardware, with the result in this thread.

Actually, the system is quite usable, with the crashes infrequent. I'm using it right now. I just don't like to work with 'flakey' equipment, since it may become 'more flakey' at inconvenient times.

But, thanks for the "heads up" from your experience with the longevity of that board.

[Scenic]

Re: Instant diagnosis of bad video board caps?

If i remember correctly, the X300 (or was it X600?) was just a refreshed Radeon 9600 for PCIe (and AGP).

Usually the ATI/AMD drivers for XP 32bit work fine on Win2k.

Worth a try to recap it, but i'm almost willing to bet it's not gonna do anything
Not trying to be mean or anything..

[RonCam]

Re: Instant diagnosis of bad video board caps?

... I've seen so many of these with faulty GPUs from running for years at 70+°C..

Ah yes, but maybe on these, they forgot to couple the heatsink to the capacitor?

Every little bit helps ...

[Agent24]

Re: Instant diagnosis of bad video board caps?

If you have room, put the new capacitor on its side and bend the leads over (don't bent right up against the body though!)

That way it won't be near the heatsink.

[kc8adu]

Re: Instant diagnosis of bad video board caps?

i chucked one of these in the recycling pile a while back.showed stripes and along with blown caps the plastic heatsink spring pins were brown from heat.

[RonCam]

Moving right along ...

Usually the ATI/AMD drivers for XP 32bit work fine on Win2k.

Good point, as that will let me replace the board and keep running while I still need the older OS.

Worth a try to recap it, but i'm almost willing to bet it's not gonna do anything
Not trying to be mean or anything..

Probably correct, and if I were in the States, I'd already have sent $24.99 - $34.99 to Newegg, get something that handles DX11. As it is, the X300 meets my basic needs, and the recapping looks reasonable compared to what I'd spend here (at least 2x the higher end of the Newegg price range) for a replacement. Besides, sounds like fun ...

If you have room, put the new capacitor on its side and bend the leads over (don't bent right up against the body though!)

That way it won't be near the heatsink.

Good idea. I've already beveled the heatsink's corner, and it no longer touches the cap. To my slight disappointment, the sharp corner was not cutting into the cap's plastic sleeve -- what I saw as evidence of that must have been a reflection in the photo. Getting the new cap farther way would be best.

i chucked one of these in the recycling pile a while back.showed stripes and along with blown caps the plastic heatsink spring pins were brown from heat.

I've had a good look at the board while removing the heatsink and beveling its corner. Surprisingly, after reading this and another report of overheating, there's no evidence of that on this board.

The case is well-ventilated, with the fan pulling air into it through a grille that blows right onto the video card. As well, my normal use puts little strain on the card.

Since cutting the heatsink away from the cap and resealing the GPU with fresh thermal paste leaves the card functionally the same as before, I will next be following the 'recapping' suggestions.

[Agent24]

Re: Instant diagnosis of bad video board caps?

I guess if you have no multicoloured lines down the screen that's a good thing.

But if it is capacitors, it probably isn't just the one next to the heatsink, if they're failing, likely all or most of them are.

Only way to know if the capacitors are bad (and if not bulging) is to measure with ESR meter and check against what they should be (although finding that out is sometimes difficult)

[RonCam]

Re: Instant diagnosis of bad video board caps?

OK, I'm ready to go with recapping the video board -- only four caps over 330uF. Is it correct, not worthwhile to bother with the smaller ones, without soldered leads?

This will cost less than an ESR meter!

With the Rubycons, I can go a little higher on the voltage specs, compared to the originals' values: with the 1000uF caps, I can go to 10v vs. the original 6.3v; with the 470uF cap I can go to 25v vs. the original 16v. I have heard higher is better, but I'm not sure if there could be problems, with this small increase, in keeping the dielectric formed?

For this fanless video card (would therefore run warmer than a motherboard), I can make a good choice from either the Rubycon or Nichicon (spelling OK?) brands. Which would be a better choice for this application, or no difference?

[PCBONEZ]

Re: Instant diagnosis of bad video board caps?

You are a little confused.
The voltage spec on a cap is just it's voltage -limit-.
The cap won't change the circuit's voltage but the rating of the cap needs to the same or higher than the actual voltage in the circuit it's in.
-
A higher voltage isn't an advantage for the voltage - it's a cheap-out trick used by manufacturers.
When they want some ESR [ESR is the goal, not voltage] they will sometimes use cheaper brand caps with a higher voltage rather than better caps with the lower voltage.
THAT is because caps with higher voltage tend to have larger cans, and larger cans tend to have better ESR for their grade.
.
In other words at whatever uF on a 5v circuit:
crap brands 10x20mm 10v with [say] .030 ESR is *cheaper* than good brands 10x16mm 6.3v with .030 ESR.
.
If you use good quality caps with low enough ESR it doesn't matter at all what the voltage rating is as long as it's enough for the circuit.
.
Now that you understand everything that's going on with it, sometimes that trick comes in handy for us recappers too.
.
The same trick works between higher and lower ESR grades also.
For instance FM is a lesser ESR grade than MBZ.
But an FM with a jumbo can might have lower ESR than a physically small MBZ with the same uF.
.
.

[RonCam]

Re: Instant diagnosis of bad video board caps?

@PCBONEZ:
Thanks! Good explanation. So, as long as I match or better the original voltage, no difference between these two options.

And, I'm surmising from your comment, keeping the dielectric formed will not be a significant consideration, by going so slightly over the original voltage specs. (By 'going over' I don't mean the board will increase its voltage in response to the cap; I just mean, the new cap will exceed, or be greater than, the specs of the old one).

Does one of these brands have an advantage over the other, on a board likely to run warmer than the average motherboard? Or no difference on this point, as well?

[PCBONEZ]

Re: Instant diagnosis of bad video board caps?

With heat issues solid polymer are the way to go if you can find some suitable.
They usually have the same max temp rating but they don't suffer from dry-out.
.

[Agent24]

Re: Instant diagnosis of bad video board caps?

If you have worries about the video card running hot perhaps you should add a fan to it?

[RonCam]

Rubycon vs Nichicon brands

If you have worries about the video card running hot perhaps you should add a fan to it?

I only brought that up because I assume it would run 'warmer' than a motherboard, and so would give the 'nod' to a brand of caps that works better under these conditions.

I just took the board taken apart to modify the heat sink, and there's no visible indication of heat damage (discoloration, or anything else). In fact, the board and components all look like brand-new.

I take it, from the comments so far, that either brand of caps would be equally suitable for this application?

By the way, the selection of caps I'm looking at, both brands, are the ones on the badcaps site.