Hello , i have bought 6 Palit Geforce GTX 750 and run them with non powered 1x riser cables over cudaminer , but they only put me ~150 khash

is anyone here using the same cards and gets them higher?

i use the following parameters in cudaminer : -H 2 -i 0 -l T4x24 -m 1

my opperating system is windows 7