An experimental FPGA board SASEBO-GII has been developed as a standard platform for advanced research on side-channel attacks and countermeasures. The board is equipped with a new FPGA device, Virtex-5 LX30/50, which provides large logic capacity and dynamic partial reconfiguration. Configuration data can be transferred from a host PC to the FPGA through a USB interface without using a JTAG cable. The USB port can also supply power for operation to the board. Even with these additional functionalities, the size of SASEBO-GII is 1/3 that of the previous board, SASEBO-G. The compactness and circuit design reduce noise that disrupts side-channel analysis. In the paper, the advantages of SASEBO-GII are demonstrated through various AES implementations and CPA experiments.