HD 7950/7970 overclocks achieved by reviewers *ultimate compilation with links*

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AnMig

Golden Member
Nov 7, 2000
1,760
3
81
Finally got my gigabyte oc 7970
default core 1000
Default mem1375
defualt voltage 1.12v

Without voltage voltage tweak
got it to 1100 core 1500 mem

with voltage (+ 100mv) 1.212v using msi beta 2.2
Maxed the slider to 1200 core 1650 mem

unable to go further since the sliders are maxed. I think there is still some headroom as other reviewers had the voltage at 1.275

What utilty are they using to get over 1200 core?

Probably will keep ot at 1200 core and 1650 mem since my monitor is onlu a 1080 27 incher
 

skipsneeky2

Diamond Member
May 21, 2011
5,035
1
71
Did not see a post or link for a msi oc edition 7970 which i got.

idle voltage 0.803v idle core/mem 300/150
load voltage 1.075 load core/mem 1010/1375

Not sure if my model is undervolted?I had what appeared to me conflicts with afterburner 2.2 causing BC2 to blackscreen hardlock my system when i go to exit the game forcing a hard reboot.

BF3 is not infected by this problem in any way.
 
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Elfear

Diamond Member
May 30, 2004
7,096
640
126
Did not see a post or link for a msi oc edition 7970 which i got.

idle voltage 0.803v idle core/mem 300/150
load voltage 1.075 load core/mem 1010/1375

Not sure if my model is undervolted?I had what appeared to me conflicts with afterburner 2.2 causing BC2 to blackscreen hardlock my system when i go to exit the game forcing a hard reboot.

BF3 is not infected by this problem in any way.

Tahiti XT was released at various voltage levels depending on how leaky the chip was. Yours at 1.075V means it is rather leaky so AMD lowered the stock voltage to come in at the same TPD as the less leaky chips. It also means you should be able to overclock well with less volts but that adding lots of volts (1.25-1.3V) probably won't show any increased headroom. This is due to the power draw from a leaky chip at high voltage overloading the VRMs resulting in instability, IIRC.
 
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skipsneeky2

Diamond Member
May 21, 2011
5,035
1
71
Tahiti XT was released at various voltage levels depending on how leaky the chip was. Yours at 1.075V means it is rather leaky so AMD lowered the stock voltage to come in at the same TPD as the less leaky chips. It also means you should be able to overclock well with less volts but that adding lots of volts (1.25-1.3V) probably won't show any increased headroom. This due to the power draw from a leaky chip at high voltage overloading the VRMs resulting in instability, IIRC.

I based my readings off gpu-z 5.9 and reading around other forums it seems other people when they blackscreen hardlock some apps like 3dmark 11 will lock up as well so this is what i did.....

I disabled ccc.exe from starting at boot,disabled the service,set up msi afterburner to run powerlimit@ 20%,i set up a manual 1125v voltage and set the core to 1025 and the memory to 1400 based off the general population and its been solid as a rock ever since.

Edit:from what i have collected,the fail to wake up from sleep bug requiring a hard reboot i believe is related to powertune and also the blackscreen hardlock.
 
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Elfear

Diamond Member
May 30, 2004
7,096
640
126
I based my readings off gpu-z 5.9 and reading around other forums it seems other people when they blackscreen hardlock some apps like 3dmark 11 will lock up as well so this is what i did.....

I disabled ccc.exe from starting at boot,disabled the service,set up msi afterburner to run powerlimit@ 20%,i set up a manual 1125v voltage and set the core to 1025 and the memory to 1400 based off the general population and its been solid as a rock ever since.

Edit:from what i have collected,the fail to wake up from sleep bug requiring a hard reboot i believe is related to powertune and also the blackscreen hardlock.

Sorry, I should have snipped the parts of your post I wasn't replying to (mostly because I didn't know the answer). Just letting you know the reason your stock voltage was at 1.075V rather than 1.175V like most others.

Glad you got your card a more stable.
 

Tempered81

Diamond Member
Jan 29, 2007
6,374
1
81
Tahiti XT was released at various voltage levels depending on how leaky the chip was. Yours at 1.075V means it is rather leaky so AMD lowered the stock voltage to come in at the same TPD as the less leaky chips. It also means you should be able to overclock well with less volts but that adding lots of volts (1.25-1.3V) probably won't show any increased headroom. This is due to the power draw from a leaky chip at high voltage overloading the VRMs resulting in instability, IIRC.

Whoa good info. How high did you ever get your 7970 to clock on liquid? And what was your stock VID and ASIC qual?
 

wahdangun

Golden Member
Feb 3, 2011
1,007
148
106
Tahiti XT was released at various voltage levels depending on how leaky the chip was. Yours at 1.075V means it is rather leaky so AMD lowered the stock voltage to come in at the same TPD as the less leaky chips. It also means you should be able to overclock well with less volts but that adding lots of volts (1.25-1.3V) probably won't show any increased headroom. This is due to the power draw from a leaky chip at high voltage overloading the VRMs resulting in instability, IIRC.

hmm isn't less voltage means less leaky chip ???

i mean the meaning of leaky chip is you can't run the chip at default setting without more voltage ??
 

Tempered81

Diamond Member
Jan 29, 2007
6,374
1
81
Yeah you're right, but Elfear is correct in his statement. And it's a long story but basically binning for a "range" of target clocks to meet the tdp while having the highest yields. Less scrutiny in binning. To get the leaky chips in there too, you have to have a broader range of VIDs, and as a result have to settle for an overall lower clock target, but you get more samples for supply. They could have cut out the leaky parts, and had lower yields and higher clocks at the same TDP, but they didn't in order to fill more supply, thus the greater range.
 

skipsneeky2

Diamond Member
May 21, 2011
5,035
1
71
Sorry, I should have snipped the parts of your post I wasn't replying to (mostly because I didn't know the answer). Just letting you know the reason your stock voltage was at 1.075V rather than 1.175V like most others.

Glad you got your card a more stable.

After more investigating and yes a couple more crash's and me making a thread about it,i had fingers from other members pointing at msi afterburner as the problem.

So i removed afterburner, put power control settings to 20%,put the core to 1050,memory to 1450 based off a link of a review actually from this thread and i haven't had a single issue period any more.

The msi oc edition card i got according to newegg is the most expensive at $600,that's also how much i paid and i guess it could have been cherry picked cards that worked with lower voltage numbers then most maybe?

Do some cards sell that have a cherry low voltage?Sorta like a super binned processor that clocks with lower voltages then normal?
 

ionic

Junior Member
Jun 12, 2012
1
0
0
Gigabyte 7970 OC Windforce 3x edition:

Stock: 1000/1375

After OC: 1285/1575 Volt 1.274

I guess 1300 is stable in most games but not in tests and BF 3.

It's a good (lucky?) chip with a good cooler (playing BF3 with OC never goes above 60c)
 

BlueEyedFrog

Junior Member
Jul 3, 2010
6
0
0
Great post(s) - really helped me with my HD7950 oc (ASUS Direct CUII).

Currently achieving (stable):
Core Volt: 1.093
Power Limit: +20
Core Clock: 1100
Memory Volt: 1656
Memory Clock: 1476

Temps are very low using Arctic Cooling Xtreme HD7970 cooler plus heat sinks (core=55c, VRM=70c when using Alien vs. Predator benchmark)

However, I'd like to go further.

Questions:
1. Should I increase mem voltage to achieve higher mem clock?
2. How do I achieve higher core clock using MSI Afterburner as it is maxed out at 1100 core clock?

Cheers
 

BlueEyedFrog

Junior Member
Jul 3, 2010
6
0
0
Actually, following the above link doesn't. While the change lets me exceed 1100 core clocks, as soon as I try to apply them, AB resets to zero and no changes are applied.
 

zaydq

Senior member
Jul 8, 2012
782
0
0
Cool thread!

I'll note that many 7950s are coming on 7970 pcbs and seem to have binned chips with 80%+ asic readings from GPU-Z. I can attest to the MSI TFIII as being one of them, since i own one. I hit 1200mhz on the core and 1800mhz on the memory with 1.168v and have been running it stable for over a month now with no issues.

http://forums.anandtech.com/showthread.php?t=2259333 <<< This is a thread I made with some pics, measurements, bench runs, overclock successes and failures + some discussion from other recent MSI TFIII 7950 purchasers with their results.

Also, i've been hearing Sapphire has taken the same route with their 7950s and should theoretically yield much better results than reviewers have gotten, especially considering they haven't taken a second look at the 7950s with the new pcbs.
 

Shmee

Memory & Storage, Graphics Cards Mod Elite Member
Super Moderator
Sep 13, 2008
7,381
2,415
146
Great work OP! nice list. If it is ok with you, I would be willing to stick this if you can keep it updated. Maybe add a second post for user oc compilation.