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Hi all,

I purchased new XFX-6950-CDDC, (Over clocked to 830MHz core clock and 1300 MHz Mem clock) card.

I am using GUIminer with flags -v -w 128 and i get a hash rate of 335MH/s. Am i using the right miner and flags?

I have tried to change the clock and power settings with AMD's catalyst software but the max i can go using the that software is 840MHz on core clock and i cannot reduce the memory clock to below 1300MHz, what tools are available to tweak voltage and memory clock? can really go down on memory clock

Also the temperature of the board is constantly in the range of 79-82 degrees centigrade[as notified by Catalyst software and GPU CAPS. I have opened the cabinet of my mother board to get more airflow. what else can i do to get the temperature down

I need tips on how to reduce my memory clock speed and also want to know if temperature of 79-82 degrees centigrade is in safer operating zone or do i need to down my core clock? what is the safer operating range for temperature.

Thanks
Pradeep

To overclock you gotta use CGMiner or enable Unofficial overclocking in MSI Afterburner as OverDrive wont let you overclock too much.

Hi Pradeep,

I also own a 6950 (MSI). My personal methodology is that both the voltage regulators (VRM) and core need to stay at 85 celsius or below. I use GPU-Z to monitor them - however do note that using GPU-Z (maybe other temperature monitors also) causes a small hashrate drop and thus temperature drop, so my policy when I was balancing the temperatures on my mining setups was to keep everything below 75c on GPU-Z while it's been open for a few minutes. Once GPU-Z closes the temperatures seem to go up a bit but 10 celsius seems to be enough of a margin.

You could also try -w 256 but if I recall correctly it doesn't make much difference on mine. I personally don't use GUIMiner anymore as it doesn't seem to get as much development these days. I recommend you checkout ckolivas' CGMiner or DiabloD3's DiabloMiner, which get regular, sometimes daily updates.

I find MSI Afterburner to be the easiest tool for modifying core clocks, fan speed, voltages, and memory clocks on ATI/AMD video cards. CGMiner also supports some of the same features but I don't know how to use them as Afterburner does everything I need.

Hope that helps mate. :)

You should avoid overclocking much more beyond what CCC will allow for if you don't have some form of additional cooling, running a miner 24/7 is much more than the normal HSF can handle, even if it's an AIB partner's special fan. I set a small 6" desk fan down and run it on high when I'm away from the computer and mining, it keeps the cards at around 82ºC with a core speed of 850MHz.

Oh, and to reduce your memory frequency, download and install MSI Afterburner (http://event.msi.com/vga/afterburner/download.htm). My pair of 6950s will only go down to 725MHz without making further adjustments which I don't care enough about to do right now. It lowered the average mining temperature of the core(s) by about 4-5ºC.

You can also undervolt with MSI afterburner, this will help your temps quite a bit.

I underclock my card (550Ti until my 5850 arrives) from 900>850 and I can run at 0.975v which reduces consumption from (at the wall) 250w down to 130w and temps from 75c down to 55c.

kind regards