Andy Brown wrote an article on reverse engineering a CPU voltage regulator:
A recent ebay fishing expedition yielded an interesting little part for the very reasonable sum of about five pounds. It’s a voltage regulator module from a Dell PowerEdge 6650 Xeon server.
I originally bought this because I had the idea of salvaging parts from it to use in another project. These are high quality modules that will have very good inductors and sometimes an array of high value ceramic capacitors that could be re-used (ceramics of at least 22µF at 16V and above are rather pricey at the moment). So the VRM arrived and I was rather impressed with the build quality and decided to have a go at reverse engineering it.
More details at Andy Brown’s blog.
Check out the video after the break.