Dell Optiplex 745 SFF PSU Recap Questions

[scruffywelder]

Hi guys

The charity that I volunteer with seems to getting a lot of small form Dell 745 (model DCCY) machines with failed PSUs. I've examined a few and the one in the (hopefully!) attached photo is pretty typical of what I've found.

The caps circled in red are visibly blown. The ones circled in green aren't visibly blown. The ones circled in blue are coated in glue and I can't see if they are blown or not.

We don't currently have an ESR meter to do a more detailed analysis.

I've put the details of the caps into a spreadsheet and (again hopefully!) attached that as well.

I've costed out doing a full recap and it looks like it would be too expensive for the charity to do, given the current financial climate and the number of PSU's we're faced with.

My questions are:-
1. Could we get away with just replacing the red ones, or are there likely to be others in among the green & blue ones that could also be troublesome?

2. If we were to get an ESR meter, would we be OK just replacing the faulty ones that we find with it? Are the caps which test out OK likely to cause major problems in the future? I ask this because, since we are a charity and the refurbished machines are being sent to various parts of Africa, we have to try to find a balance between affordability and service life.

3. What is the white glue/sealer that is used in PSUs for? Does it need to be replaced after recapping? If so, what works?

Thanks in advance for any help.
Cheers, Scruff.

[DJduck]

Re: Dell Optiplex 745 SFF PSU Recap Questions

No glue replace needed. You should replace all caps, but you can just replace the bad ones and see if it works. If no, replace all. What brand caps are in there?