The longest I have been able to get my rig to run is 12 hours. I don't know what's causing it, but it's freezing up and I have to do a hard reboot which isn't convenient since I normally use team viewer. I posted my settings at
https://bitcointalk.org/index.php?topic=623409.msg7036775#msg7036775 if anyone can look at them and give me some suggestions. If the miner was just crashing I wouldn't care so much because that's easy to restart. It's just the hard reboots that are killing me.
Working on figuring out settings for gigabyte r9-270's still, I'll post when I find a good config that runs for an extended period. I also use teamviewer...someone needs to make a power strip that can be toggled on and off remotely over the internet....That would be a lifesaver.
The second set of settings in my Gigabyte R9 270. It's been running great since yesterday. Right around 2.2 Mh/s.
"auto-fan" : true,
"temp-cutoff" : "85,85",
"temp-target" : "73,75",
"gpu-fan" : "55-100,75-100",
"xintensity" : "512,512",
"vectors" : "1,1",
"worksize" : "256,128",
"lookup-gap" : "2",
"thread-concurrency" : "8192,5121",
"shaders" : "1792,1280",
"api-listen" : true,
"api-port" : "4028",
"api-allow" : "W:127.0.0.1",
"expiry" : "120",
"gpu-dyninterval" : "7",
"gpu-threads" : "2,2",
"gpu-platform" : "0",
"gpu-engine" : "1170,1200",
"gpu-memclock" : "1500,1500",
"gpu-powertune" : "20,20",
"log" : "5",
"no-pool-disable" : true,
"queue" : "1",
"scan-time" : "60",
"shares" : "0",
"kernel-path" : "/usr/local/bin",
"kernel" : "x11mod"