Help needed replacing capacitor

[3vilc]

Hi all,

I have a laptop that I am trying to fix. The problem is a blown capacitor on the power regulator board. There are no markings on it anywhere. I have measured a similar cap on the board at 10uF so im using this as a base for replacement. However, I am unsure what type of cap to replace it with, it looks like a small chip about the size of an 8pin IC. Looks like a surface mount tantalum and being a computer circuit i would assume it is, but tantalums are polarised and there are no marks on the old cap or the board as to a + or - side (other caps like electros on the board are marked on the + side). It appears the only caps available upto this size in, and in a small enough physical size are electros and tantalums, both of which are polarised. I have already tried a bipolar electro and that didnt work.

Can anyone offer any help, can i do much further damage trial and error fitting a tantalum, other than blowing the new cap if its round the wrong way

Thanks in advance
Clive M

 

[Nigel Goodwin]

Why do you suspect it's a capacitor?.

 

[3vilc]

it is labled as ''C40" and it measures as being 10uF on a multimeter

 

[Styx]

you really cant measure capacitors in-cirucit, the capacitor meter will real the capacitance across the terminal. This will inclue the capacitor you are measuring plus any other capacitance seen by this point

 

[3vilc]

the measurement was done with the component unsoldered from the board. also measured by soldering a quick voltage divider circuit and calculating the capacitance, the results of which where confirmed by my friends meter (mine doesnt have a capacitor function
so we established it is a capacitor, just trying to replace it.
looking at websites which sell surface mount components it only looks like a tantalum, yet all the ones I can find are also polarised and as I say the board doesnt appear to be