Bitcoin Forum

just picked up two powercolor 7970 v3 today, and its voltage is unlocked (both direction)
but I can't manage to make it hash over 600K

get 600K with reaper
get 550K with CG 2.11.4

I try to keep the 0.57 ratio and set the core to 970 and memory to 1700
it's stable at 1.063v but the hash rate is not ideal.. :'(

Where's Tacotime when you need them...

Check that user's sig, they have a link to tuning your GPUs for Litecoin mining.

thats why most guys buy 7950 for LTC mining ...

gpu threads 2
worksize 256
thread-concurrency 8192
intensity 13

(or
--thread-concurrency 8192
-g 2
-I 13
-w 256
in cgminer)

Core voltage 1.087 v
Memory voltage stock
Core 1051 MHz
Memory 1744 MHz

drivers: 13.1
SDK: 2.8

722 KH/s

donations always appreciated. :)

it's interesting, yesterday I lower the core to 912 and the memory clock to 1600,
and lower the -w to 128, @ 1.063v one card can mine stable at 600
and the other at 550.....

seems they have some different quality?
or LTC mining has some dependency on how good the rig is? I mean I am running it on a 775 platform with 4G of DDR2 RAM
does this impact the speed?

true, my 7950 with reasonable OC can mine at 550, and some ppl use their MSI WC mine at 600
but the price of a MSI WC is almost the same as the 7970 I got...... :P

I find that this will not work for certain 7970s.  I have one that does not follow any of the rules put forth, just like ryan's.

It is a visiontek 7970 that will not go above 610Kh/s regardless.  Even stranger memclock changes do nothing for the hashrate, only engine clock changes which con said couldn't happen.  Really weird.

I have a Sapphire Radeon HD 7970 OC with unlocked voltage..

Using Sapphire Trixx to adjust settings im running right now around 700.. trying to push it a bit more but slowly..

settings for the card are.. 2nd bios setting

gpu 1175
memory 1040
vddc (voltage) 1231
boost 20

I think i can push the gpu and voltage a bit more tho..

after about 1 hour of tweak.....
I finally found sweat spots of these two cards.
for me the 0.57 ratio is the highest I can set for core/mem
I finally set the ratio to be 0.55 with core @ 915
now both mining @ 620-630
@ 1.018 voltage

so I guess it's still energy efficient at this speed.

I have stock 7970, 2 per rig and on each rig one runs around 600mhash but the second is always around 370 to 420mhash.

Played with memory clock, gpu, v, I... But no changes - any idea for optimal settings?

Currently using settings from guiminer-scrypt as is and modified gpu to 1130 and memory to 1050 as found on wiki.

Any help appreciated, would love to get close to 2600 / 2700 Mhash rather than the average 2000 I am getting now.

Are you doing litecoins, have you tried cgminer by itself?

What card do you have..

Keep in mind that work size (-w) for litecoin mining on a 7970 does not need to be changed.  This information is directly from the man who programmed it. (CKlovias)

And people - keep in mind when someone gives you advice like this, do NOT overlook details like the drivers and SDK that are being advertised.  I know it seems minor, but at the end of the day - its anything BUT minor!!!!!!! :D

EDIT:  Also - I have managed to get lower on the voltage while still being stable.  It all depends on your card, but don't be afraid to experiment!

being the owner of 5 7950's (all gigabyte) and having got my first 7970 yesterday (sapphire dual x)... 7950's are ABSOLUTELY the winner for value.


650 on a 7950 vs 710 on a 7970... its a no-brainer..

the 7970 i'll use as a gaming card this summer when i shut down my mining due to heat :)

Agree, heard some 7950 can hash > 600, but my reference cards only stays at 550 or I haven't find their sweat spots.

However price wise those "healthy" 7950s are also pricey, I remember the MSI 7950 is about $300 each (without any AMD Promo coupon or AIR), so I end up pay about  $25 more for a 7970, that's after tax and delivery :)

Last thing I haven't figure out is, with lower core/memory frequency to achieve same hash rate, say 630Kh/s, does this mean a 7970 consume less power than a heavy OC'd 7950? (I saw my friends OC their MSI 7950 to 1050 core, 1700 memory to get about 610Kh/s @ 1.1xx voltage, compare with my 7970 with 920/1672 @1.018)

I have the same Powercolor card. The main issue you're going to run into is that the cooling solution sucks balls. I have 7 other 7970s running at 680 kh, but that one can only run at 550 to keep it cool. I had the same issue with it mining BTC. Other cards at 1110 / 170 pulling 640 mh/s, but that one could only run up to 1080 and it was running at 100% fan.

are we talking about the same card?
this is the one I am referring to
http://www.powercolor.com/us/products_features.asp?id=398

I have some different experience with these cards, the 7970s I have can mine with little noise at 630 each and it keeps the temp at 70 (the one closest to the CUP) and 68 for the other one. (my wife even ask me to sell all my reference 7950s to get all this kind of 7970, noise really kills her :D )

Exact same card. My 6870x2 failed and they sent me that as an RMA replacement for it. The rig that cotains this card has 3x7970s in it. I have this card on a riser where the other two are onboard, but as far away from each other as possible. Ambient temperature ranges right now from 67-80 F in an extremely well ventilated space. The two onboard run 675 kh around 55-60% fan while this card can't even hit the clocks necessary because it overheats. With the fan at 100% the card keeps getting warmer, warmer, and warmer, until I have to close cgminer to let it cool down. Perhaps, I got a lemon, but out of my 7970s (6 visiontek reference, 1 sapphire dual fan, and this powercolor) this one is easily the worst. Noise, doesn't bother me as my rigs are a on the first floor, but if it was I'd go with this card: http://www.newegg.com/Product/Product.aspx?Item=N82E16814102982R . I bought it open box last year and it easily the best in regards to noise, cooling, and the ability to overclock.

Well, if that's a replacement from RMA, the chance is that's a repaired card....so they maybe fixed something and screwed up something else.  I am sure you have already swap position with the onboard cards, maybe another RMA?

Today I got my 2x Gigabyte HD7970 OC cards.

They are running on the following settings:


Hashrate is nice good enough  :)

http://i146.photobucket.com/albums/r254/MaGNeT76/smooth7970_zps99b004dc.jpg

nice card, specially the temp is good.
my cards can only work at about 630,  :(

What version catalyst drivers and sdk are you using? That same number only gives me 500 kh. I've tried all sorts of numbers that other people have posted with multiple versions of drivers. The only decent results I've found so far have been catalyst 13.3, included SDK, cgminer 2.11.4, 1025/1800 (Agression 13 =  590 / 20 = 675) with this config file:

"intensity" : "20,13",
"vectors" : "1,1",
"worksize" : "256,256",
"kernel" : "scrypt,scrypt",
"lookup-gap" : "0,0",
"thread-concurrency" : "24000,24000",
"shaders" : "0,0",
"gpu-engine" : "0-1025,0-1025",
"gpu-fan" : "0-100,0-100",
"gpu-memclock" : "1800,1800",
"gpu-memdiff" : "0,0",
"gpu-powertune" : "0,0",
"gpu-vddc" : "0.000,0.000",
"temp-cutoff" : "95,95",
"temp-overheat" : "85,85",
"temp-target" : "75,75",
"api-port" : "4028",
"auto-fan" : true,
"expiry" : "120",
"gpu-dyninterval" : "7",
"gpu-platform" : "1",
"gpu-threads" : "1",
"hotplug" : "5",
"log" : "5",
"no-pool-disable" : true,
"queue" : "1",
"scan-time" : "60",
"scrypt" : true,
"temp-hysteresis" : "3",
"shares" : "0",
"kernel-path" : "/usr/local/bin"

a quick question, does it really matter which crystal/SDK to use for 7900 series cards?
I haven't paid any attention to this.

For what it's worth, I have a 7950 clocked at 1175/1200 with 1.25 Vcore. If I restart my computer and start mining, I get about 350 mh/s. However, if I open CCC and change the power control settings to +10% then my hashrate goes up to around 615. I am on the newest beta driver with no SDK installed, so maybe it's just a bug? Something to try if you're getting a really low hashrate anyway.

protip: sometimes AMD drivers or the card get REALLY wonky and slow down like 10% from where it should be.

It has happened to me before and is happening again. I have 2 rigs with the exact same cards but 1 is getting 570 each while the other is getting 630 each (same settings and OC)..

to remedy: I imaged my windows install.. did a fresh install.. reinstalled drivers.. restored my old install.. and bam.. it was back to normal.