Hi, im new minning, i tried few month ago using sgminer5-0-1, as adviced because i have a v card AMD Radeon r9 270x, everything worked fine and i tested making some transactions, i mined dgb-groestl.

Currently i've tried to run again the sgminer (i stoped minning for about 2 moth) but now im getting a cople of warnings:
[22:41:30] WARNING: GPU_MAX_ALLOC_PERCENT is not specified!
[22:41:30] WARNING: GPU_USE_SYNC_OBJECTS is not specified!
then my screen freeze and show no picture and have to reboot my system.

Any idea what is wrong? i downloaded the sgminer twice again and re configured but still the same problem.