Underclocking Memory Speeds Correctly on 7xxx Series Cards With Afterburner

[tacotime]

12.6+ AMD drivers do not let you change the memory speed of 7xxx (7950, 7970, etc) cards below a certain threshold.  To underclock memory, use Afterburner and a dll file.

1) Install MSI afterburner.
2) Download this dll file and place it in your Afterburner directory.
3) Edit the afterburner config text according to this thread and set unofficial overclocking mode to 2.
4) Run MSI Afterburner.
5) Set the overclocking mode to kernel instead of software in settings.
6) Underclock memory as per usual.

It took me a long time to figure this out from various threads, so hopefully now people will find it easy.  This also allows you to overclock memory above the overdrive maximum.

[ummas]

Thx for the hint.
I passed and installed linux, but now i can go back

[gigica viteazu`]

+1 tacotime

now i`m able to lower the memory to 525 on my single 68xx card

[meebs]

dangit tacotime... if ANYBODY on this forum deserves donations thrown at them on a daily basis.. you are one of the few!

Great guide. I am now rocking lowish memory speeds (like 500-600ish, not sure how some folk are getting 200...)

[Cablez]

If you have multiple cards just switch between them while applying the memclock changes each time. The slider will reset.

If you only have one card then you will have to close afterburner and restart it after each memclock adjustment.

[tacotime]

^^  yup.

the weird thing is that works for some cards and not others.  i have an xfx 7950 that works fine on, but my gigabyte 7950 will only go down to 650mhz alone.  if i put both cards in a system i can use that trick to underclock the memory of the xfx card and then check off the box that says "use the same settings for similar cards" to get the gigabyte card's memory down, but otherwise i can't.

[Cablez]

That is really weird. I have never had a card that couldn't be adjusted that way.

Maybe its a BIOS limitation?  Did you ever check to see what the lowest setting for memclock in the BIOS is using RBE?

[Shermo]

On my 6870 and 7950 I have to set the memory in afterburner to lowest (640?), then close it, reopen then I can set it lower down to 300

[Tinua]

On my 6870 and 7950 I have to set the memory in afterburner to lowest (640?), then close it, reopen then I can set it lower down to 300

On my Club-3D HD6870x2, I have to do the same and its working.
But on my Club-3D HD7970, I can not go down! The driver crash allways.

[CrazyGuy]

If you close afterburner after setting the lowest mem clock, then reopen, you can slide the memory down further. I open and close Afterburner twice to get my 7970 memclocks down to 185.

[EPiSKiNG]

This isn't working for me with 12.8 and MSI Afterburner 2.2.4 on 7970s of all different types... I put the DLL file in the MSI folder... Any ideas?  I get limits at 700 and 685, depending on the card...

THANK YOU FOR THE HELP!!!
-EP

[crazyates]

This isn't working for me with 12.8 and MSI Afterburner 2.2.4 on 7970s of all different types... I put the DLL file in the MSI folder... Any ideas?  I get limits at 700 and 685, depending on the card...

THANK YOU FOR THE HELP!!!
-EP

Go into the MSI program folder, and delete all the files in the PROFILES folder.

[Gatorhex]

There is a reason for limiting the underclock...

..if you underclock memory too far you end up with a computer that won't boot up!  

How to use MSI Afterburner...
At the bottom are some numbers 1 2 3 4 5 this is where you can store your settings.
There is a tick box to apply your setting at startup (don't tick this until you are sure it works)
In "advance settings menu" MSI lets you switch between multiple cards to change each one and also unlock the safty settings.

[jjshabadoo]

good stuff. need to try it soon.

[EPiSKiNG]

Crazy weird... I have two setups, almost identical...  Miner1 has 2x Asus 7970 with an old Intel chipset, Miner2 has 2x Asus 7970 with the 990 AMD chipset.  Miner 1 allows me to underclock memory, but miner 2 wont work!  I've copied and pasted the CFG files, neither of the rigs has catalyst control center installed, and they both have 12.8...  Perplexed...

-EP

[tacotime]

yeah, i'm not sure why stuff like that is.  the ability to control the memory speeds of the cards has been really wacky in afterburner since 12.6+ drivers.  You may want to report it as a bug.

[Fiyasko]

Hmmm. I WOULD do this, But my hashrate starts to crap out when my memclock goes below 740...

[crazyates]

Hmmm. I WOULD do this, But my hashrate starts to crap out when my memclock goes below 740...

Play with the settings then. I'm at 1050,410 on my 7970, and it takes a full ~2 minutes to finally stabilize at a hashrate, but it's pretty stable.

[scifimike12]

crazyates, what is your hash rate at 1050/410?  I'm currently using 1050/300 and getting 631 Mh/s.  Just trying to compare.

[sveetsnelda]

Hmmm. I WOULD do this, But my hashrate starts to crap out when my memclock goes below 740...

You're using a weird kernel or APP SDK version then.  All of my 7970s run at 340Mhz, and the hashrate is pegged.  In fact, I'm sure it could run lower (but I don't know how stable it would be).