Identify a Mobo Alu Cap (help!)

[12AX7]

Hey all,

 

Got an Asus Crosshair III Formula of which a few (alu closed) caps had been sidebashed and they need replacement. I suspect them to put the board into a 'usb over current protection' state of automatically shutting down within 15 secs (yes I checked USB etc.). Three of them, all the same value. I just can't figure out what I can get as replacement. The cap says the following:

 

FP

OZBx (the O could be a 'zero')

101

16

 

Can someone give me some kind of advice...want to get this board going.

 

Thanks, Michel

[der8auer]

Should be 16 Volt with 101 µF

 

edit: If you can't find the correct capacity you can just go for the next step higher or something which is close. Shouldn't matter that much

Edited November 17, 2016 by der8auer

[elmor]

USB over-current protection is normally caused by the resettable fuses being blown. If you're sure they're triggering for no reason you can try to short them manually. First check that all of them (black/white SMD parts marked with P) have 5V on both terminals. If you find one that doesn't this should be where your problem lies.

 

[12AX7]

Most excellent, thanks guys. I did however make a mistake...it's a Crosshair IV Formula . I have both, made a typo! If you could post a pic with meassuring points for the IV that would be awesome

 

Values gotcha! . The caps were stretched quite a bit to the side putting significant force on the Cap legs and I pushed the caps back, so I would expect the problem to be one of the caps causing a short. Could I just desolder the 2 'suspicious' caps and try without them to see if the error is gone? Need to replace them anyways...but if it doesn't hurt I could already verify it.

 

Also, I can use normal caps as well I guess...if I can get the Alu locally I will, but they might just have the regulars.

[elmor]

Can you show which caps?

 

[12AX7]

Most excellent!

 

I tried to attach the pic...

 

Great!, so I have a bunch of fuses I need to meassure for voltage....if one has blown it will show. But if a cap is busted and is internally shorted, I should still have voltage on all fuses I guess?

Edited November 18, 2016 by 12AX7

[elmor]

Most likely those are stabilizing caps for 5V USB. Any 100uF 16V cap will do as replacement. If one of those caps is bad it's very possible it's causing the USB overcurrent issue you're seeing.

[12AX7]

Very good!

 

ok...this repair is new for me so bear with me as I want to understand exactly what I am doing to be able to figure it out myself if needed. Sooooo, just took out the board and the multi, and the 'breaker' (that's what they are right?) closest to the reset button only has voltage on one side. I will meassure all of them, but as this is the problem area I found the failing element quickly. Left side shows 5. something volts, the right hand side nothing.

 

What is the best way to move forward. Can I bypass the breaker safely just to test, or should I start with replacing a certain cap or the three caps alltogether? Something caused the breaker to fail, if the cap is the suspect root cause I have to replace the caps anyways...educate me plzzz

[12AX7]

Just got rid of a few Mobo's, but I have a Z77A-G43 which is broken and has 16V 100 caps on it. They are a tad smaller in height, but they should do fine right? Just don't want to mess up the Formula!

[elmor]

Yes that should be fine. You can check which fuse it's connected to by measuring the resistance between one of the capacitor pins (the one that's not connected to ground). But I think the cap should be connected to the side that still has 5V, so probably the capacitor is ok. I think it should be ok to short the fuse in order to test it, you don't have any peripherals connected there correct?

Edited November 20, 2016 by elmor

[12AX7]

So short it by hand and see what happens...if it runs, solder a fixed bridge or simply add a new breaker. The fuse is there for Voltage I take it, but it probably has a wattage rating as well. I presume I can simply put a new fuse parallel on top of the broken one. Comes to question if caps that were bent like on the picture can actually work if you push em back. In case it is just the broken fuse it would probably be caused by a faulty USB device...can't really think of anything else. I really was suspecting them caps though:

 

Edit: Really need to read up on the Mobo subcomponents...been primarily focused on straight component repair, pin jobs, power sections and memory for modding . Fun too, and if I can get it to work I'll be grinning for a couple of days !

Edited November 20, 2016 by 12AX7

[12AX7]

Report!

 

Well I went ahead tonight with some further TS...and I thought if the fuse is broken I should not be able to meassure resistance, but on all I could meassure a value. Then it had to be the cap, and I replaced the obvious one closest to the fuse that had the failing voltage. A pain to get a nice clean hole, but once soldered I fired it up and bang...no failure message ....yeah baby! I made a BIOS with USB disabled and flashed it before I started looking into soldering, that seemed to have worked like a charm. Instant OC from scratch setup in the BIOS...if it wasn't so much hassle you'd want that for each of your boards....babbling along in my exstatic state lol

 

Thanks a lot for the good help, learned a few things on the way...easy to overthink things when you are on unknown grounds. Now for the big test with the 8350...see how she holds up under a decent load

 

Thanks again, you rule, Mies