$ ./benchmark_tx.py -f 450e6
--tx-amplitude=0.05 -r 500k --tx-gain=30 -m dqpsk
linux; GNU C++ version 4.6.1;
Boost_104601; UHD_003.004.000-06d0032
>>> gr_fir_ccf: using SSE
-- Opening a USRP1 device...
-- Using FPGA clock rate of
64.000000MHz...
........................................................................................U.............................................................................
.......................................................................................................................................................................
.......................................................................................................................................................................
.......................................................................................................................................................................
.Segmentation fault