How to lower memory clock to really low speeds?

[chungenhung]

I've read people running their memory at 200MHz. How is that achieved?
The lowest setting on MSI AfterBurner is 500MHz for a 5850.
And every time I set it to anything below 600 is crashes.
How are you guys achieving such low memory clock rates?

[goatpig]

5850s don't like super low memory clocks.

As for MSI AfterBurner, you're supposed lower the ram to its lowest available setting, close it, then reopen it and you'll have lower settings available.

On 5xxx series, you can use AMD GPU Clock Tool, where you simply type in the value you want and set it.

[xarchangelzerox]

I'm having trouble with this as well, same card. (5850)

Every time I try and set the memory clock to around 300mhz, and then restart (either just afterburner or my whole computer) afterburner never remembers my memory clock settings.  No matter how many times I click apply and save, once the program restarts, it puts the memory clock at stock.

I've even tried editing the profile config files by hand and making them read only so afterburner can't change them, no luck. 

The core speeds and voltages never get messed up, but the memory clock just won't stick.  How do I fix this?

[Clavulanic]

What's the idea behind keeping memory clocks super low? I realize GPU memory speed has little if any effect on mining, but I would imagine lowering them THAT low would affect mining. Am I wrong in that assumption?
If you can mine at the same speed with such low memory clocks that is awesome, you'd end up saving a good deal of electricity and lower your GPU temps.

[clonedone]

What's the idea behind keeping memory clocks super low? I realize GPU memory speed has little if any effect on mining, but I would imagine lowering them THAT low would affect mining. Am I wrong in that assumption?
If you can mine at the same speed with such low memory clocks that is awesome, you'd end up saving a good deal of electricity and lower your GPU temps.

ive lowered both my 6990s to 650 from 1250 mem clock speed.
mining rate did not change, nor did the temp or the noise.
cant tell if its using less electricity, but i hope so

[nster]

http://bitcointalk.org/index.php?topic=4292.0

[chungenhung]

What's the idea behind keeping memory clocks super low? I realize GPU memory speed has little if any effect on mining, but I would imagine lowering them THAT low would affect mining. Am I wrong in that assumption?
If you can mine at the same speed with such low memory clocks that is awesome, you'd end up saving a good deal of electricity and lower your GPU temps.

ive lowered both my 6990s to 650 from 1250 mem clock speed.
mining rate did not change, nor did the temp or the noise.
cant tell if its using less electricity, but i hope so

I always though lower memory speed will increase mining speed.
If mining rates did not change, then I guess I will just keep mine memory at default speed.

[nster]

What's the idea behind keeping memory clocks super low? I realize GPU memory speed has little if any effect on mining, but I would imagine lowering them THAT low would affect mining. Am I wrong in that assumption?
If you can mine at the same speed with such low memory clocks that is awesome, you'd end up saving a good deal of electricity and lower your GPU temps.

ive lowered both my 6990s to 650 from 1250 mem clock speed.
mining rate did not change, nor did the temp or the noise.
cant tell if its using less electricity, but i hope so

I always though lower memory speed will increase mining speed.
If mining rates did not change, then I guess I will just keep mine memory at default speed.

Many people have seen speed increases when lower mem clock, as well as temp drops of 10C+ and over 10% savings in power usage

[humble]

I lowered the mem speeds on all mine to 300 yesterday (5870, 5970 and 6870" and immediately noticed almost 10C drop in temperature and a slight increase in speed (about 5MH/sec). Great little tweak.

If you have AMD 5xxx+ cards and are running Linux this is a great tool:

http://sourceforge.net/projects/amdovdrvctrl/

[nster]

I lowered the mem speeds on all mine to 300 yesterday (5870, 5970 and 6870" and immediately noticed almost 10C drop in temperature and a slight increase in speed (about 5MH/sec). Great little tweak.

If you have AMD 5xxx+ cards and are running Linux this is a great tool:

http://sourceforge.net/projects/amdovdrvctrl/

try tweaking further if you have to... on that 6870, try 320, or 340 maybe

[twitcoins]

I have a 5830 clocked at 1000/195.  I had heard good reports of people at 300 (slight increase, better temps) and so I just started backing it down a little at a time.  I'm also using AMDOverdrvCtrl.  There's probably a 'sweet spot' on just about every card, and there may be more than one local maximum.  But yeah, I drop off by a half Mhash or two either side of 195 @ 1000.

[humble]

I lowered the mem speeds on all mine to 300 yesterday (5870, 5970 and 6870" and immediately noticed almost 10C drop in temperature and a slight increase in speed (about 5MH/sec). Great little tweak.

If you have AMD 5xxx+ cards and are running Linux this is a great tool:

http://sourceforge.net/projects/amdovdrvctrl/

try tweaking further if you have to... on that 6870, try 320, or 340 maybe

Thanks, I'll give it a try next time I'm at that machine!

[humble]

I lowered the mem speeds on all mine to 300 yesterday (5870, 5970 and 6870" and immediately noticed almost 10C drop in temperature and a slight increase in speed (about 5MH/sec). Great little tweak.

If you have AMD 5xxx+ cards and are running Linux this is a great tool:

http://sourceforge.net/projects/amdovdrvctrl/

try tweaking further if you have to... on that 6870, try 320, or 340 maybe

I took another look and I'd set it to 350. I guess I'd tried 300 and hadn't been happy. Changing it to your recommended 320/340 gaves me another 1mh/s. Thanks!

Always feels good to know that things are at maximum efficiency.