i am already using new algos 
What settings did you have to change from x11/x13 if any? I got my 260x running no prob 780Kh with my x11/13 .conf and my x4 270 rig is running 1.3Mh a card with my old settings also. Usually steady at 2Mh a card with x11, am I close?
I was getting much better speed from my 260x than 780kh/s on X11/X13.
Try these settings, should work with the new algos as well:
gpu-engine: 1150
gpu-memclock: 1500
xintensity: 120
worksize: 64
hamsi-expand-big: 1
darkcoin-mod for X11 should yield 1050kh/s
marucoin-mod for X13 should yield 950kh/s
ps. i set thread-concurrency to 8000 for this GPU for scrypt/-n, it is also set the same for x11/15 but shouldnt matter. for scrypt and scrypt-n, gpu-engine should be 750 for the 260x.
On x11 I get 1.2mh with the 260x using these settings:
"xintensity" : "120",
"worksize" : "128",
"kernel" : "x11mod",
"lookup-gap" : "2",
"thread-concurrency" : "12100",
"gpu-threads" : "2",
"gpu-engine" : "1150-1150",
"gpu-memclock" : "1250",
"temp-cutoff" : "95",
"temp-overheat" : "85",
"temp-target" : "75",
"api-mcast-port" : "4028",
"api-port" : "4028",
"expiry" : "28",
"failover-switch-delay" : "60",
"gpu-dyninterval" : "7",
"gpu-platform" : "0",
"log" : "5",
"no-pool-disable" : true,
"queue" : "1",
"scan-time" : "7",
"tcp-keepalive" : "30",
"temp-hysteresis" : "3",
"shares" : "0",
"kernel-path" : "/usr/local/bin"
}
I did change from intensity 15 to x120 though, wasn't a huge pick up in hashrate but a much happier computer. Best I have managed so far with x15 is just over 800kh using the same settings except intensity 17. On the 270's I'm still at 1.4 but getting a lot less hw's. Haven't had much luck stopping them, still searching for more examples for x15.
