Replacing capacitors with different value

[sansonet]

Im trying to fix motherboard that has some bloated 1800uf caps , but I have only 1500uf available. I temporary replaced 4 bad ones to see if it will fix problem, and it did, so now I want replace it correctly.
I cant figure out is they in series or parallel? I have lot of similar motherboard 1500uf caps, 1200uf, 1000uf and less, also some 3300uf.
Is there any way I can make proper combination with what I got? There also one empty spot that can be used to add extra cap.

[petehall347]

Re: Replacing capacitors with different value

order the right ones .they arent expensive

[sansonet]

Re: Replacing capacitors with different value

I know, but really would like to get done with it now and not wait for shipment to arrive.
If they in parallel, I could just use all 1500uf caps and extra one in empty spot, that will give the same total. Just hard to tell on this motherboard how they are connected.

[ChaosLegionnaire]

Re: Replacing capacitors with different value

just use a multimeter and probe for continuity on the positive through-hole for each cap spot.

[sansonet]

Re: Replacing capacitors with different value

That was first what I did, but they beeping in any combination - between legs of the same one, legs of different two, in any positive/negative variation, only slight difference is in resistance.
Any way, I was able to find some 1800uf caps, 16V ones (originals are 6.3V). I still might order some new ones too.

[Stefan Payne]

Re: Replacing capacitors with different value

Depends on where you use them. The believe that you need the right capacity and everthing is fine is just a lie!

The truth is, you have to look at the original caps and take a look at what the hell they used here:
General Purpose, Low ESR, Low Impedance, Ultra Low Impedance. ANd of course the ripple current.

With these information you can think about replacing the caps.

Since we're talking about a CPU VRM thingy, you should go high ripple current and low ESR, don't care too much about the values...

WIth that I'd go for 6,3V or maybe even 4V polymer capacitors, if at all possible. Because there aren't any other lowest ESR Options available...
In theory even 2,5V ones should be fine. Since that board looks like an AM2 one. And they just don't do well with 2V or more CPU VCore


Buttom Line:
Capacity isn't that important.
ESR and Ripple Current is.

It would be fine if you use smaller caps with lower ESR and higher ripple current.

[sansonet]

Re: Replacing capacitors with different value

WIth that I'd go for 6,3V or maybe even 4V polymer capacitors, if at all possible. Because there aren't any other lowest ESR Options available...
In theory even 2,5V ones should be fine. Since that board looks like an AM2 one. And they just don't do well with 2V or more CPU VCore

It is AM2 CPU, but motherboard is almost 10 y.o., I dont really want spend lot of money or time on it. I use Linux mostly and with 2.6GHz CPU and 4GB ram it works fine and fast for what I need, but it still old and I dont know how much longer I will use it until I'll feel like upgrade.
Here is discussions about the same board and more details on old caps https://www.badcaps.net/forum/showth...ght=MCP61SM-GM