I am using the wiznet w5100 on one of my projects and I can't figure out how to get it to work when I am powering my board from an external power source. I have made a custom board that I am using, this is not through an arduino board. I have an "arduino breadboard" and the w5100 on my custom board. The arduino has a 5v voltage regulator and the w5100 a 3.3v regulator before it. Everything works fine when I am using an ftdi cable to power my board, however when I switch to the external power the w5100 stops working. I do not get any led indicators on the mag jack, and no response from ethernet requests. I have check the voltage on the power pin of the w5100 and I have 3.28v... I have attached an led to another pin of the arduino and ran a blink test through it and the atmega seems to work fine from the external power. Any ideas would greatly be appreciated.