If i have 2 cards, can use only one card to mine, and the other to play for example?
really mi idea is put a RX 470 with claymore dual etherum and R9 270 with claymore for zCash
Yes you can. In claymore you have -di option so you can set for instance -di 0 and only first card will mine.
-di? where?
setx GPU_FORCE_64BIT_PTR 0
setx GPU_MAX_HEAP_SIZE 100
setx GPU_USE_SYNC_OBJECTS 1
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_SINGLE_ALLOC_PERCENT 100
EthDcrMiner64.exe -epool us1.ethermine.org:14444 -ewal 0x2a5C5a860fde542e8ef14673F14E38Dd90242104.work1 -epsw x
setx GPU_FORCE_64BIT_PTR 0
setx GPU_MAX_HEAP_SIZE 100
setx GPU_USE_SYNC_OBJECTS 1
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_SINGLE_ALLOC_PERCENT 100
EthDcrMiner64.exe -epool us1.ethermine.org:14444 -ewal 0x2a5C5a860fde542e8ef14673F14E38Dd90242104.work1 -epsw x -di 0