caps replaceing..

[wizard james]

well, got a bad cap on a motherboard i just got for free, i was going to be ording a large order from mouser soon, so i wanted to know a few things about what to get.. for my voltmodding goodness.

i want to spend around 20-30 dollers so i got some stock.

one thing i do need is a 6.3v 3300uf cap. i have no idea what any of that means.. so can soemone help me out here? maybe i can replace whats on the motherboard (thats leaking) with a better one? .. i donno..

also going to be volt modding my nf7-s so.. i will need a few of the things for that and what not.. thanks for the help anyone can give

[four4875]

the uf (u on the cap is actually a micro sign) stands for micro farad, and is the rating of how much energy it will store. the voltage is the max operating voltage it will run at, and it can be increased without changin how the circuit acts. It appears that you can put larger capacity caps in the board and it wont affect its operation, so almost anytihng should be fine. But it would be best to get osmetihng the same as the one you're replacing. it should probably cost the same and would be best to fit in with the reg.

the site or catalog should have ones the same in there, just grab one of them.

[wizard james]

ok, i notice this one here: http://www.mouser.com/index.cfm?handler=displayproduct&lstdispproductid=651773&e_categoryid=324&e_pcodeid=74000

is 5 dollers for just one, and this one here here (http://www.mouser.com/index.cfm?handler=displayproduct&lstdispproductid=288323&e_categoryid=500&e_pcodeid=64710)

is under a doller, whats the diffrence?

[KorbenD]

The $5 one is a tantalum surface mount capacitor, which really isn't what you'd want. The second is an electrolytic.

You need a low ESR electrolytic capacitor, with equal uF rating, and equal or higher voltage rating. While you can often go higher in microfarads, I'm not sure I'd try it with a motherboard.

So, if you have a 3300uF 6.3v capacitor, a 3300uF 12v will work fine, just as long as there's enough room for the capacitor to physically fit on the board.

One thing though: Avoid Nichicon brand capacitors like the plague. They're the brand of caps that's causing Dell all sorts of headaches with premature failure.

[wizard james]

i see, so is there one that u can recommend?

i can seam to find the right one..or a good one at that site

[TazExtreme3]

Avoid Nichicon brand capacitors like the plague. They're the brand of caps that's causing Dell all sorts of headaches with premature failure.
that's cause dell uses the cheapest ones they can get, I'd recommend one of these two
http://www.mouser.com/index.cfm?&handler=data.listcategory&D=647-UVZ0J332MPH&terms=647-UVZ0J332MPH&Ntt=*647UVZ0J332MPH*&N=0&crc=true
http://www.mouser.com/index.cfm?&handler=data.listcategory&D=647-UPW0J332MHH&terms=647-UPW0J332MHH&Ntt=*647UPW0J332MHH*&N=0&crc=true

[cyberey66]

Try and find computer grade capacitors. The noticeable difference is they usually have 105 and the degree symbol written on the side. I got some from a local electronic store, radio shack didn't carry anything high quality. The voltage rating doesn't have to match at all, as long as it is greater than or equal to the rating on the original. ie, for a 6v cap, you can replace with a 6v, 10v, or 15v etc... The voltage is always the same across the capacitors regardless, the rating is just the highest it can handle.

Make sure to note the polarity too. If you have a capacitor bank, row of the same capacitors, you can vary the capacitance as long as the total capacitance of the entire amount is the same. ie, 3x 1000uf caps = 2x 1500uf caps. This is assuming in parallel, ie positive to positive, negative to negative. Just try to find about the same capacitance.

Replacing caps is simple, and chances are everything will work again afterwards.

[KorbenD]

While Nichicon is usually a decent brand, they had a LARGE production lot of capacitors that fail to meet their stated temperature rating. Quite a number of them ended up being used in Dell SX270, GX270, and GX280 motherboards.

So far this year, I've changed out over 200 motherboards (under warranty, thank goodness) in those models. Every single one had Nichicon caps that were bulging upwards, leaking, or simply exploded. Rubycon caps right next to them, same uF, voltage, and temperature rating, were fine. I've had five more fail just this week. I expect the problem to continue until basically all the 270 boards have been replaced, or the PCs have been lease swapped out.

Based on that, and the fact that there's really no way to know which run of caps you're getting, I still advise *not* buying Nichicon. You just might get one of those bad ones, and you'll never know until it starts bulging upwards and you get random crashes.

[KorbenD]

Here (http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/searchPage2.jsp?Ntt=rubycon&newSearch=true&searchtype=keyword&Nty=1&N=0&Ntk=gensearch) is potential a source for Rubycon caps. While they don't show a current stock, I've never had much trouble with their lead times. I don't know if/what the minimum quantity is.

Also, this (http://export.farnell.com) company lists them as well. I checked a few common values, and they show as in stock. Might be worth checking out.

[wizard james]

i see, and thanks for all the help..

tobad i cant find a place in canada or the usa. ..maybe i will look a little more ..

but sofar ..this is one of the things i can find. http://export.farnell.com/jsp/endecaSearch/partDetail.jsp?SKU=769095&N=401
but its from overseas.. so it will cost alot for just 1 cap.

haha, and i was just looking at a older dell motherboard.. and it has a rubycon cap on it.. tobad its not the one i need.

[four4875]

remember, you dont have to get rubycon specifically, anything butthe nichicons should do, as long as they live up to their specs you'll be fine. mouser.com should be fine.

[KorbenD]

Yep, any decent brand should do. I just posted those sites for another user (who deleted his previous post) because he was having trouble finding Rubycon.

[ThePCGuy]

Hmm :). I like my nichion capacitors. Time will tell I guess.

Replaced caps with nichion on the following:

8khal+ (GSC)
8rda+ (GSC)
8kha+ (GSC)
8k7a (GSC)
8k7a+ (GSC)

All 5 of them work great.

[ThePCGuy]

Well what do you know, I've got more nichion caps coming in. My Slot A Athlon 500/MSI MS6167 Combo died on me. I've got roughly 13 capacitors coming in to replace the bad ones.

Dead caps:

(2) Chhsi 1000uF 10V
(1) Chhsi 470uF 16V
(10) Chhsi 470uF 10V
---
Parts should be in by Monday, if they are in by Friday, I'll have it done Friday night. I'm hoping I can get this one back as I had just started it folding. I wouldn't mind buying extra for stock but I already have quite a few 2200uF 10V caps left from the Epox boards, and I'm seeing lots of various capacitance rated caps on these boards. And it is only costing me $10.00 total for the caps. Of course the caps are only $3.83, but shipping is about $6.00. Anyways, I'll let you know how it goes.

- Jim

[ThePCGuy]

Forgot to post back. She's up and running like a champ. I've got two more boards on their way to get some open heart surgery done. I can't wait to find some cpus to use on these boards (they keep accumulating). One's a KT266 Soltek board, the other is a nForce Soltek board. Should be fun.

- Jim