6950 dilemma - breaking 320 MH/s

[darkskypoet]

Short description:

Currently running GUIMiner v2011-06-09

Top scores seem to be running it standard,  no flags (which uses poclbm)   --device=0 --platform=0 --verbose


Every time i try and play around with Phoenix - no matter the settings:
-k phatk , VECTORS, FASTLOOP=false, BFI_INT, Workspace=XXXX, AGGRESSION=11 or 12 etc, etc...
I don't even get to the same level as just stock no option poclbm.


Is this normal???


All the suggestions i've gleaned from around the forums say Phoenix should be faster, and that the extra flags yield higher scores... and yet on my XFX Radeon 6950 1gb @ 840 core... Can't breach 310-320MH/s. and Pheonix with phatk gets me 275HM/s ish

Any ideas? My second 6950 is arriving shortly... so would like to eek out some extra without cranking the core clocks up.

Thanks

[1715104150]

1715104150

[danw635]

320 MH/s is about what I was getting with a stock 6950.

I unlocked the shaders and flashed the bios to a 6970 and now I get 400+MH/s.

Core Voltage is at 1200mV
Core Clock is at 950MHz
Mem Clock is at 850 MHz

The fans have to be on hairdryer mode or you'll melt the card, but it's worth it.

Im using   -v -f30 -w128   for flags in GUIminer.

[darkskypoet]

Interesting, perhaps with the unlocked shaders the -v and -w128 actually increase performance, with normal shader count and core @ 840, it drops performance... hmm...

[darkskypoet]

Well downloading MSI Afterburner to see what I can get that way. And thinking about it... I am guessing that the flash running in th background of the websites I am on is probably cheating me of a few MH/s as flash accelerates on GPU... should close my browser when i leave. lol.

Bah MSI Afterburner will only give me up to 840 as well.. sigh... I unlocked the overclocking in the cfg file as well.. but I think I have to put a string in the line above it... Just misplaced the post that mentioned it. Perhaps flashing when i have more time.

[danw635]

Flashing takes 5 minutes.

http://www.techpowerup.com/articles/overclocking/vidcard/159

Just make sure you only have 1 card installed at a time when you run atiwinflash.

[darkskypoet]

Already there.. its complaining about a P/N mismatch between the bios I pulled off the card, flipped the unlock switch on, then went to flash back on to it... So Was just reading up in their forums before i forced it through atiwinflash.

[accod]

Check in Afterburner if the clock speed is fluctuating whilst mining.  You might need to increase the power settings on the card to +20% in ccc.

[computerparts]

Already there.. its complaining about a P/N mismatch between the bios I pulled off the card, flipped the unlock switch on, then went to flash back on to it... So Was just reading up in their forums before i forced it through atiwinflash.

Do you even know if your card is a model that can be unlocked? Seeing as how it's a 1gb version, I don't think it can be unlocked.

[Waltibaba]

hey,
to optimise performance with the 6950, try following my steps posted here: http://forum.bitcoin.org/index.php?topic=14962.msg200573#msg200573

You can unlock the upper limits in both MSI afterburner and CCC overdrive, for overdrive the method is more complicated but I find it much more stable and efficient. That method is outlined here: http://www.overclock.net/amd-ati/954528-all-radeon-6950-only-flashing-shader-5.html#post12819472
Happy mining!

[darkskypoet]

Already there.. its complaining about a P/N mismatch between the bios I pulled off the card, flipped the unlock switch on, then went to flash back on to it... So Was just reading up in their forums before i forced it through atiwinflash.

Do you even know if your card is a model that can be unlocked? Seeing as how it's a 1gb version, I don't think it can be unlocked.

It's iffy... many of the xfx ones can be.. but by modding the bios, not using the posted 6970.. however if they hardware fused the shaders, then no.

here's hoping.

[darkskypoet]

Well... So I found out some kind of disparaging news...

My XFX HD - 695X - ZNFC lacks the Bios switch to go from the backup protected to main unprotected bios for flashing purposes...

Further, there is some talk that it can be flashed, however one has to short a couple pins on the bios chip itself, as it is locked by default, and needs a hardware override to allow flashing. On top of that, it is undeterminable if after all that... that the shaders will even work if unlocked.

Sigh.

I like XFX... even though they are just Pine... but still, this is balls. Had I known this i wouldn't have bought from them, and would've gone asus, or sapphire even.

[dinzy]

Short description:

Currently running GUIMiner v2011-06-09

Top scores seem to be running it standard,  no flags (which uses poclbm)   --device=0 --platform=0 --verbose


Every time i try and play around with Phoenix - no matter the settings:
-k phatk , VECTORS, FASTLOOP=false, BFI_INT, Workspace=XXXX, AGGRESSION=11 or 12 etc, etc...
I don't even get to the same level as just stock no option poclbm.


Is this normal???


All the suggestions i've gleaned from around the forums say Phoenix should be faster, and that the extra flags yield higher scores... and yet on my XFX Radeon 6950 1gb @ 840 core... Can't breach 310-320MH/s. and Pheonix with phatk gets me 275HM/s ish

Any ideas? My second 6950 is arriving shortly... so would like to eek out some extra without cranking the core clocks up.

Thanks

I have similar performance.  -w128 doesn't do anything, -v drops 10%  I also don't get much of a push with OCing it. 

In MSI Afterburner what is a good voltage to try for OC? 

[darkskypoet]

Have you gotten MSI Afterburner to unlock? I was unable to get it to let me push past the 840mhz that CCC gives me. Although, I finally tracked down the string you have to type in to the cfg file when you set the overclocking option to 1... I just have to find it again

[ovoskeuiks]

I have a sapphire 1G 6950, it is the same no dual bios and bios is locked
I got the soldering iron out and hooked the Write Protect up to VCC and am able to flash the bios
However it appears the shaders are disabled on chip as it has made no performance difference.

I am still curious about modifying the GPU overclock limits by flashing but am a little reluctant due to having only one bios chip
Has anyone increased the limits by flashing?

[darkskypoet]

I am pretty sure that's roughly the same process as I'd have to use with my XFX card. You may have to mod the bios in order to up the overclock limits on the card... but from what I found in RBE, it recommended grabbing those settings from another bios, rather then just changing the limits (which it allows you to do) in case the card isn't recognized after that... So it may cause problems, but is probably reversible, unless you can find another bios to pull the heightened speed limits from. Have you tried unlocking afterburner and seeing what speeds you can achieve with that?

[dinzy]

320 MH/s is about what I was getting with a stock 6950.

I unlocked the shaders and flashed the bios to a 6970 and now I get 400+MH/s.

Core Voltage is at 1200mV
Core Clock is at 950MHz
Mem Clock is at 850 MHz

The fans have to be on hairdryer mode or you'll melt the card, but it's worth it.

Im using   -v -f30 -w128   for flags in GUIminer.

Are you sure this is Apples to Apples?  I have a locked and an unlocked one on 2 different rigs.  The locked one gets 350, the unlocked one gets ~ 360.  Both run at ~ 900 MHz.  In gaming the unlock is only supposed to net about 3% boost yet you got 25%.  Something else must have changed.  Perhaps it's your OC.  950 is pretty good. 

[darkskypoet]

Well I am hoping to get the crappier xfx one to at least clock up to 900... and the Asus one I just received has the bios switch, and is probably unlockable... but.. its just a shame that the xfx one is neutered like that.

However, considering that it's summer, and the one 6950 running all out warms the room up noticeably... perhaps I'll be happy with both churning away at 840ish in crossfire. Don't exactly want to have to have the fans going more then 75-80%.

[ovoskeuiks]

Running it in a linux box so haven't been able to try afterburner or anything, I will have a look for a signature from another 6950 does anyone know of one with higher than 840 peak GPU?

[supermine]

I'm happy I cancelled the 6950. Shaders are everything.

[darkskypoet]

Running it in a linux box so haven't been able to try afterburner or anything, I will have a look for a signature from another 6950 does anyone know of one with higher than 840 peak GPU?

The Asus one i just got has a 950 mhz top out in CCC, haven't tried going much over 850 with it yet though... i'll let it burn in first. Also, I am gonna try and see if an unlockd MSI AB will let me go past 840 on the XFX.


Shaders aren't quite everything... power usage, efficient use of your type of shader, and achievable clock all count as well.