Yesterday, my sheeva died after 6 months of non stop usage. It was connected to an APC 1500 VA UPS system with output 240v/50Hz (along with other devices). and with a 2TB jbob system of 2 3.5'' HD. I opened the PSU and found out that the output capacitor (1000uf/6.3v) was blown. I am not sure about the health of the voltage regulator but to be on the safe side I will change this also. I think that the design of the power supply is relatively simple and there is no need for a complete schematic in order to repair it. The only components that can not be easily replaced are the 2 transformers, but I suppose that this will rarely happen. If for some reason the replacement will not succeed then I will follow the external PSU solution.