Three blown caps - Asus maximus 3 formula

[Jens]

Hi

My friend has a Asus maximus 3 formula. But it was getting unstable. He thougt it was the videocard that was making the computer to freeze and bluescreen so he bought a new videocard. But the computer still bluescreened and freeze so he bought a new psu with more power (corsair 750w). But after hooking up the new psu and started the computer three caps got blown away from the mainboard(sounded like a firecracker).

My question is. Do you think its possible to replace the bad caps and nothing more is damaged on the mainboard. Is it worth a try?. And i need to know what caps to buy. I can't read out what caps being used.

I will get the mainboard and cpu(i5) for free so it would be nice if i could fix it myself. My friend bought a new mainboard and i7 so there is nothing wrong with the new psu.

The ones i have marked with a red ring is the caps that got blown away
http://zerox.myftp.org/~jens/blandat/maximus.jpg

Thanks for any help i can get.
/Jens - Sweden

[Koda]

It is possible that the board is undamaged except for the capacitors but you really need the markings of the capacitors so you know what to replace them with and you need to replace all of the capacitors surrounding the cpu. If you decide to replace the caps take note in which way the caps are placed on the board, Asus likes to reverse polarity markings on their boards. Also some pics of the board would be helpful. BTW getting an i5 and a mobo for it for free is sooo cool

[Jens]

I will see if i can get a picture of the mainboard in a few days. Problem is that when the caps exploded the metal housing of the caps got destroyed. So i need to find a good picture of a working mainboard so i can find the correct replacement caps.

[mariushm]

Yeah, you'll have to get the board and post some pictures, closeups of those spots.

I did some snooping around and found a review with closeup pictures of those areas:

http://www.overclockersclub.com/revi..._formula/3.htm

I can see in the pictures most capacitors have FP in the name which makes me think it's the short for "Functional Polymer" , a sort of hybrid polymer capacitors made by Nichicon.
The capacitors on this board are probably a custom series made for Asus, as Nichicon doesn't make them in this washed out gold style.

Going through the closeups around the CPU, I see on the thinner caps 101 16v, which is 100 uF 16v.

On the top of the board I see one that says 271 16v, which is short for 270uF 16v - in another picture with capacitors near the back connectors I see a capacitor that has a code which starts with 2, so I assume that's also 270uF or 220uF 16v.

As they're all 16v, it makes me think they're "energy reservoirs" for the voltage regulators which convert 12v to the voltage the processor needs, and the capacitors closer to the socket are probably rated for maxim 2.5-3v and store the actual energy that goes to the CPU.

The old power supply probably started to give 12-14v or maybe even spikes over 16v, adding a lot of stress on these 16v capacitors and they crapped out.

So based just on this information so far, you probably have to get 270uF 16v and/or 100uF 16v polymer caps, with high ripple and low esr values...

Trying the Sweden site of Farnell...

This might be the actual series Asus branded in their colors:

http://se.farnell.com/nichicon/rl81c...ial/dp/1853463

You see the FP on the picture ... otherwise the picture is not correct, they just snap a photo of some random capacity/voltage combo in the series.

In the worst case scenario, these *may* work, but specs wise, they're about 2 times worse than those polymer caps (still way better than other electrolytics)

http://se.farnell.com/panasonic/eeuf...0uf/dp/1800683

Yes, it's 50v rated and a bit wider at 10mm, but this is to get the specs as close as possible to the polymer caps.

As for the 100uF 16v, you can get these:

http://se.farnell.com/united-chemi-c...16v/dp/1687418

and this *may* work as it's relatively close to the polymer capacitor specs:

http://se.farnell.com/rubycon/35zlg1...35v/dp/1805449

[Per Hansson]

It's very strange for solid polymer capacitors to fail like this.
Please use a power supply tester to test that new PSU.

It is likely faulty and testing it with another mainboard will just blow up that too.
Under the heatsinks on the mainboard next to the capacitors that failed there will be MOSFETS.
Take a look at those, if they are cracked the price to fix the board will probably be too high...

[Uranium-235]

these are "functional polymers" (mentioned above). WHY does asus have to cut corners on such a high end board? I would figure custom poly caps would cost MORE then normal polys

[NormanSaxon86]

first off great board and I hope you can make use of your friends board. I will be in for this one I can wait to see this one completed.
You could call Asus and ask where you can get the same CAPACITORs. More pictures of progress please.

[NormanSaxon86]

Also I would like to see pictures of the Asus maximus 3 formula Catastrophic failure.

[Agent24]

Originally Posted by Per Hansson

It's very strange for solid polymer capacitors to fail like this.

Maybe but it's happened before.

(Though like the others said, it's probably FP)

http://www.xtremesystems.org/forums/...osion-of-P5K-E

[mariushm]

It is functional polymer:

[belippy]

that guy replaced the 270uf 16v with a 1000uf 16v?
does it work?

[Agent24]

maybe it did work, but probably not a good idea, that's over 3x larger than the original value. Of course depending on what actual function that capacitor performs in that circuit might mean that the increase was perfectly OK.

[Jens]

Sorry for a late message. I replaced the three bad caps with regular 330uf 16v caps. Instead of 271uf 16v. But the where also some bad joints under the mainboard that needed fixing to. But the mainboard works again. So i am happy =). But it was really hard to get the solder to melt so i could remove the bad caps.

I forgot to take pictures of the fixing.

[Agent24]

Originally Posted by Jens

I replaced the three bad caps with regular 330uf 16v caps. Instead of 271uf 16v.

Great! As long as by regular you mean 330uF and not some general purpose grade capacitors.

[Jens]

I replaced the bad caps with these

https://www.elfa.se/elfa3~se_sv/elfa...7-233-73&toc=0

Instead of http://se.farnell.com/nichicon/rl81c...-20/dp/1853463

Because my local dealer had the first one in stock and they only cost 12 sek for 4 pieces without any extra freight.

The computer have been running fine over the weekend. No bluescreens or crash so far.

[Agent24]

Suncon is Sanyo so the quality should be fine, looks good! Should last a long time.

[c_hegge]

That's a Sanyo WX electrolytic. Good quality, but not nearly good enough spec-wise to replace the original caps. As I've said in other threads, NEVER EVER buy your motherboard caps from local electronics stores. They rarely sell suitable caps for use on the VRM of a modern board.