E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

[mshaw]

Hi I have the following motherboard and it has a broke off capacitor the 2.5v 820UF yellow/black i have searched and searched for a replacement with no luck i came to a post on these forums suggesting "better to recap with reliable 1500uF 6.3v Ultra Low ESR E-Caps, instead of these old yellow Fujitsu polymers." im wondering if that is best for my situation and if im going to do this to the 2 capacitor will be be fine or will i need to do this to all 22? Thanks!

[davmax]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

Try forum member Bigpope for a replacement polymer. He will send by email.

Damn, he has gone on Chinese new year holiday for three weeks. Pity.

Perhaps somebody on forum will help you out with one polymer.

[PCBONEZ]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

"better to recap with reliable 1500uF 6.3v Ultra Low ESR E-Caps, instead of these old yellow Fujitsu polymers."
-
Probably not better.
The Fujitsu probably have ESR ratings <.010 and correspondingly high ripple ratings.
-

Where are you located?

.

[mshaw]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

I'm located in Kansas city Missouri I've got 24 6.3V 820UF caps I'm wondering if it would be alright to install just one or best to replace all 24?

[mshaw]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

Not that it will probably make a difference but I mean replace all 22.

[Harvey]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

Have you tried the board? With just one capacitor missing out of 24 it should still work fine.

[kc8adu]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

if same brand/series just 1 is safe.1 missing should not hurt either.does it still post?

[starfury1]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

well if you just broke one off then you will probably get away with just replacing the one with no worries "preferably same type (brand series)"

As harvey said it will probably work fine without it anyway, but ideally replace it

Is that MB dual CPU with 3 lines of caps 2 X 7 ...1 X 6
( a crop below)

They look like part of the VRM those 3 lines

if your soldering skills are not the best then thats further reason not too...go read the FAQ's and learn how to use the needle for hole clearing
(or dental pick) practice on junk first.
Thats possibly a nice MB and you don't want to stuff it.


Generally speaking

If they were your normal Electrolytic caps and one or two had popped (Failed)
then yes replacing all would be advised.

I myself,
would probably replace the line if it was one in the line
Just so they are all at the same age and type but thats me.
"Especially Type" so they share somewhat equally,
Ideally you dont mix and match in VRM circuits

dose depend on how the circuit put together I suppose too

if its an odd ball somewhere else on the MB (the count is 20) so seems there must be 2 more scattered may be near memory slots.

Then yeah no worries at all

I suppose it does depend on its use too...how far you want to go

HTH Welcome and Cheers

[mshaw]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

It is that exact motherboard from your picture. And looking at that picture it is the very bottom far left yellow cap 2.5V 820Uf like i said the best replacement i can find for it is the 6.3V 820UF. I need to do what ever im going to do with it in the morning because it needs to be in service by afternoon. so if anybody can tell me the best thing to do in this situation i would appreciate it. Thanks

[mshaw]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

Also. This motherboard is Brand new never used the cap broke off because in the box i had it in the heatsink for the cpu hit it and knocked it off. so all other caps SHOULD, and do look to be ok.

[mshaw]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

One more Also... I have not tested the motherboard yet I found the cap floating around the bag and decided it was best to fix it now.. its going to be used in a data center and as little problems as i can get from it would be best.

[PCBONEZ]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

Give me the numbers off both the wayward and prospective replacement caps.

.

[mshaw]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

original cap has a little m and then below that is... 34267. and the new caps i bought from jameco SKU number 607355. MFG# UPW0J821MPD

[starfury1]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

this is probably a bit late but I'll post it anyway

sounds like thats a "mission critical" use so yeah Id fix it "same with same" or post replacement you going to use as above

check MB for any pcb damage (sounds like you done that but should be mentioned anyway)

The below is just really leaning on the side of "caution" and putting in place with a cap gone it might do 2~3 without a hiccup at all
probably really ,more so depends on the demands of the CPU

Again "not the expert" on this and no idea on that dual MB
but to my way of thinking

it would work with another suitable cap but you have somewhat comprised the integrity of the MB VRM

sound like too the replacement cap (820uf 6V3) is an wet electrolytic so you maybe better not to use it, or use 1500uf
(if its a polly then (more so) fine)

None at all might be best.
and just get a suitable replace and pull it when you can for service and replace same with same

it should work with one missing just slightly worse performance and possibly shorter life span for that part of the circuit

another option

I doubt there is a same type cap used else were on the MB but if there is
maybe switch it to that broken position and use the replacement in its position. (if they are wet electro's use a 1500uf this would have an ESR more in line with a 820uf polly there abouts anyway)
(the 3 lines should all be same type)

mixing caps in VRM circuits is "not" recommended.

Again no expert and there are others here who could answer this question much better then I

anyone thinks I got it wrong then please post corrections

Cheers

[starfury1]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

no idea on the caps numbers...over to you pcbonze your better at that then me
(or anyone else for that matter that knows)

BTW I am assuming its the bottom line on the left hand corner as the cap that got ripped off
but any in those 3 lines should all be the same type, series, ideally

[gdement]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

Too late to be helpful I'm afraid, but digikey has Nippon PSA polymer caps in those specs. They should be 8mm according to the datasheet, don't know what diameter your board's pads are laid out for. I have some 680uF PSA's, but not the 820's.

Jameco doesn't have any normal electrolytics that are very suitable for motherboards (unfortunately). The PW caps you bought are the grade you'd find on a Pentium-2 board, but not something this modern.

Not sure if it's better to add the PW in parallel with those polymers, or just leave the pad empty. I'd be inclined to leave it empty, I don't know what having that PW in there would do to it's behavior.

It looks like all those polymers are probably in parallel to filter Vcore, so leaving 1 pad empty out of that many total will most likely not cause any problems. It should be designed in anticipation of the caps degrading as they age, so the loss of 1 cap should be within it's tolerances for the time being. If the CPU in the adjacent socket isn't near the board's limits, then there'd be even less cause for concern.

Assuming reliability is more important than the money, the best solution might be to order a replacement board, quickly swap it out at an appropriate time, then fix the cap on the other board when you find the right substitute (or just sell it off).

original cap has a little m and then below that is... 34267.

Not sure what that number is, but the "M" sounds like Panasonic. If it's by them, it should have a capital M in a little box.

If it broke off like that, the caps might be surface mounted, not through-hole. That would make replacement more tricky/dangerous because you have to solder at the top of the board.

[starfury1]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

actually thats another point top mounted and I dont know how strong a polly is on through hole leads but I dont think it takes much to knock one free that are the top side mounted type things.

I think the idea is if you got all the same type then the ESR is going to be very close with them (in parallel as you say) but if you have one that a little higher it wont be able to deliver as much current and the heating affect will be more on that cap.

It may also generate a slightly higher ripple

The VRM feeds the current to them at a controlled rate at startup so thats not really an issue per say,
but I think if it senses voltage across the caps as part of control
(and I dont know that it does??? forgotten what little I read on how they work)
The odd ball with higher ESR might trip it sooner before the others have come up fully charge wise. (maybe that works in reverse humm the others charge up before it does)

Thats pure speculation and I could be totally wrong on that.

Now we are really going into "The how a VRM works" and probably the chicken and egg thing too.

regardless of the case in point which kicked of the thread
A little bit of discussion on this might be warranted cause solid polly's are becoming the norm for this position.

lastly I thought they might have been wet electro's as he mentioned 6.3 Volt I didnt know if they were or not.

Anyway just my thoughts and it doesn't help solve you problem mshaw

leave it off fix it latter as above might be the simple best solution.

cheers

[PCBONEZ]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

As I read back I see I have already explained this two weeks ago.
[So don't tell me this is urgent now... ]

As I said:
The original cap is Fujitsu with a very very low ESR rating.
-
The M = Tolerance = +/-20%
34267 is only a date code.
Historically Fujitsu does not mark the series because the ESR is so so low it doesn't really matter.
ESR is probably .007 and Ripple between 5000 and 6000.
-
UPW0J821MPD is a PW series which is barely a low ESR cap.
ESR is .085 and Ripple is 730.

You will need 10 or 11 UPW0J821MPD to handle as much Ripple as that one Fujitsu does.

As gdement said, Digikey has PSA series polymer caps that will work.

.
.

An old quote I like:
Lack of forethought and planning on your part does not constitute and emergency on my part.

[starfury1]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

so basically not worth trouble of using that cap anyway as its unsuitable type
(read as pointless really)
thanks pcbonze

[PCBONEZ]

Re: E7501 Master-FRM Motherboard 1 Broke off 2.5V 820UF capacitor.. Need Advise!

http://search.digikey.com/scripts/Dk...me=565-3057-ND

APSA2R5ELL821MHB5S
2.5v 820uF 8x11.5mm ESR=.007 Ripple=5580