I've noticed now that not all of mine like the 1200/1200 clocks from that previous post... If one of my machines hangs with the settings below I've switched them to 1130/1400 clocks which all of them seem to be ok with. I don't feel like wasting the time to set the GPUs individually, lol. I've also changed thread & intensity settings since the new version with support for higher intensity was compiled. I now run:
"gpu-vddc" : "1.155",
"gpu-threads" : "2",
"gpu-fan" : "75-100",
"gpu-engine" : "1200",
"gpu-memclock" : "1500",
"gpu-powertune" : "20",
"kernel" : "x11mod",
"temp-target" : "75",
"temp-overheat" : "88",
"worksize" : "64",
"shaders" : "1280",
"thread-concurrency" : "5121",
"xintensity" : "500"