Are you still powering the board the same way? Make sure to use the correct power supply. Also have you already used the firmware update tool on your board? It can be found in http://www.intel.com/support/galileo/sb/CS-035101.htm named Intel® Galileo Firmware Updater Tool. There is also a new developer Kit http://www.intel.com/support/edison/sb/CS-035180.htm that installs the latest IDE and drivers. Have you already installed it?