I'm running an R9 290, and here's my settings:


I get 375-380 KH/s, which I suppose is decent, but sometimes when cgminer starts up, my entire system crashes.  It'll say cgminer is starting, then the window goes blank like its about to start, but then my system locks up.  I can move my mouse, but clicking on anything does nothing.  Alt-Tab and CTRL-ALT-DEL do nothing.  After about 15 seconds in this state, my entire screen goes black, and it stays in this state until I manually power off my computer.

But it only sometimes does this.  And when it works, it'll work as long as I need it to.  Once its running, its perfectly stable.  It is only the initial start-up that has an issue.