How to prevent overheating the gpu with bfgminer 3.10

So ' I'm trying to mine mazacoins using bfgminer, but the problem is that the gpu quickly reaches 90 degrees celcius, the manufacturing specs recommend to not go over 85 (radeon 6870).

Using the bat file I've used these parameters:

setx GPU_MAX_ALLOC_PERCENT 75
setx GPU_USE_SYNC_OBJECTS 1
bfgminer.exe -o stratum+tcp://maza.cryptoadhd.com:4444 -u xxxx -p xxxx -S opencl:auto
--auto-gpu --auto-fan --temp-overheat 80 --temp-target 75

That did nothing, gpu still reached 90 degrees. So I tried the config file

{
"pools" : [
   {
      "url" : "stratum+tcp://maza.cryptoadhd.com:4444",
      "user" : "xxxx",
      "pass" : "xxxx",
      "pool-priority" : "0"
   }
]
,
"intensity" : "8",
"vectors" : "2",
"worksize" : "128",
"kernel" : "phatk",
"lookup-gap" : "0",
"thread-concurrency" : "0",
"shaders" : "0",
"gpu-engine" : "0-0",
"gpu-fan" : "0-85",
"gpu-memclock" : "0",
"gpu-memdiff" : "0",
"gpu-powertune" : "0",
"gpu-vddc" : "0.000",
"auto-fan"
"auto-gpu"
"temp-overheat" : "80",
"temp-target" : "75",
"api-mcast-port" : "4028",
"api-port" : "4028",
"expiry" : "120",
"expiry-lp" : "3600",
"gpu-dyninterval" : "7",
"gpu-platform" : "0",
"gpu-threads" : "2",
"log" : "5",
"no-pool-disable" : true,
"no-show-processors" : true,
"no-show-procs" : true,
"no-unicode" : true,
"queue" : "1",
"scan-time" : "60",
"skip-security-checks" : "0",
"submit-stale" : true,
"temp-hysteresis" : "3",
"shares" : "0",
"kernel-path" : "C:\\Program Files\\BFGMiner\\/share/bfgminer",
"scan" : [
   "opencl:auto"
]
}

And still the gpu reaches 90 degrees. I've tried including the intensity parameter in the batfile and put that to I 8.

If I mine other coins the temperature is always controlled using intensity. Any ideas?