according to your discussion, "The maximum data rate of the AD9957 parallel port is 250Msps, which equates to an I/Q pair at a 125Msps rate. Hence, the maximum modulated bandwidth is 125MHz".
I really like AD9957. It's really perfect QDUC-DAC chip. but in my project, bandwidth is 160MHz. could you please offer me other QDUC-DAC part number ? (to support my project bandwidth)