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Other => Beginners & Help => Topic started by: psycosis on November 02, 2011, 09:15:14 PM



Title: 6950 poor performance
Post by: psycosis on November 02, 2011, 09:15:14 PM
Hello,

I have a stock 6950 and i am getting only 250mh/s from it.
I have the most uptodate ATI drivers and it will not go up, i was under the impression this should be a lot faster without any changes.

Anyone got any ideas what could be up.

Thanks


Title: Re: 6950 poor performance
Post by: jake262144 on November 02, 2011, 09:20:27 PM
Miner and parameters?
Operating system?
Is it a dedicated rig or your workstation? A web browser running some flash will totally demolish your mining speed.

EDIT: You should be getting at least 310 Mhash out of this thing using any contemporary and well-tuned miner if it's a dedicated mining card.


Title: Re: 6950 poor performance
Post by: psycosis on November 02, 2011, 10:11:28 PM
Using Guiminer on windows 7 x64
not using any special params and this is a workstation so i don't want to mess too much.

I noticed Saphire have handly included a switch which already unlocks the shaders. So in this mode its running 800mhz and 1536 shaders. i now get 318.
this is still with the stock settings.

If i use -v -f30 -w128 then i get 352.9mh/s
What exactly are these commands changing?


Title: Re: 6950 poor performance
Post by: jake262144 on November 02, 2011, 10:17:40 PM
318? I'd call it close enough for government job, would you agree? ^^
You might try OC'ing it a bit, just because it's a decent card you got there.

These paramters are used for fine-tuning the miner to your card.
The -w parameter is the work size which can range from 64 to 256. Generally, for a 6950 the optimal value is 128.
-v enables vectors. You DO want to do this.
-f is for tuning the mining aggression (basically, the load on your card); the LOWER walue here, the more aggressive the mining.


FYI, GUIminer is but a frontend - the actual miner (down below the pretty gui) is, in your case, poclbm.
Below you can see the current source code for poclbm, all possible parameters, their default values and meaning are explained there:
https://github.com/m0mchil/poclbm/blob/076f85c63d1ce21c81695eed9b60eb778a0f1ade/poclbm.py

Good luck!

PS. In your first post, you were like "i don't want to mess too much"
      After a while you added the "-v -f30 -w128" string
      Dude, by this rate tomorrow you'll be building a dedicated mining rig :)


Title: Re: 6950 poor performance
Post by: psycosis on November 02, 2011, 10:26:08 PM
I think its close enough too.
Surprised that without unlocking those shaders the card isn't coming anywhere near the stock figures. i think this is due to the card running a lower cpu speed for some reason. It didn't seem to be running at 800Mhz properly.

Case is on its side due to space, so i will leave it at that.


Title: Re: 6950 poor performance
Post by: RyNinDaCleM on November 03, 2011, 01:21:10 AM
Try running CGminer with -I 8, and leave out the -v -w128. Those are the default settings.


Title: Re: 6950 poor performance
Post by: MyZhre on November 03, 2011, 09:59:47 AM
I got about 390MH/S with GUIMiner/OpenCL, Win7


Title: Re: 6950 poor performance
Post by: portron on November 03, 2011, 02:39:50 PM
I think its close enough too.
Surprised that without unlocking those shaders the card isn't coming anywhere near the stock figures. i think this is due to the card running a lower cpu speed for some reason. It didn't seem to be running at 800Mhz properly.

Case is on its side due to space, so i will leave it at that.

Just use the ATI CC (the official tool) and up the clock speed a little.  You won't damage your card or anything.  I have a couple 6950's each pull ~375-380.