I've been using a few Arduino Pro's (5v) for a couple of months now and have been programming them with the 5v FTDI Basic from Sparkfun. However, I changed USB cables and now the board does not power on properly. It either turns the power light on and then off and thats it. Or the power light flickers constantly when connected to a different computer. I've tried different boards and cables. I can't find the cable I used to connect to the board originally. Is there a more specific USB mini cable that I need to be using? Or have I done something to the board itself? As above, this configuration has worked before for me.