Another dumbass question: Has anyone run multiple instances of miner clients and had it stay stable. I want to use seperate cards in same box so I can try Vertcoin. I realize I might have to upgrade memory capacity for that box. I know cgminer has an option to select cards to use ... just have not dug into it yet and do not want to make my mining box unstable trying this.
I use a separate instance of cgminer for every card, it works fine. Just specify the device and device platform in your code. This is the only way to run different cards at different settings on the same box anyways, as far as I know. You will need to run "cgminer -ndevs" once to
it is not the only way of running different cards (sg and cg-kalroth allows you to run any amd cards in one rig with one miner running), but it is the only way to distribute yout hashes among different pools like one card for vert, one for heavy, one for wp, one for cm, one for cs and one for ghio.