ATI underclocking memory under linux?

[supa]

I've got 6950s and 6970s.

RBE warns on certain changes that the native drivers may stop recognizing the card.. and someone else mentioned after a certain RBE edit even aticonfig wouldn't find the cards.

Are you using a signed 'rbe' excerpt from another card (~1kb) to get around that?

As already mentioned, make sure you make a backup of your existing BIOS.  atiflash has a built-in command (-s X filename).

I don't bother with the RBE signatures, etc - I just change my clocks under Additional Settings with relatively good luck so far.

The only "issue" (really not an issue) is that on reboot after flash, Windows did infact not recognize the card.... and I had to go through letting it re-detect and put the drivers back in place.  Occasionally, it would do that every 3 or 4th reboot.  I stopped using Windows whenever possible....  

PS - for the record, ^ the above only happened on one Windows PC and a buddy with an identical card doesn't have that problem.

[darkpandora]

Even leaving AMDOverdriveCtrl running, same result.. the displayed ranges of --odgc make it look like lower clocks are possible, but below some threshold which varies based on CPU clock any change (from --odsc or GUI) doesn't take effect and in fact causes the memory to snap back to the default for the current load level. Arrrgh!!!

I'm having the same problem.

i have the same problem too on my 6990s

Adapter 0 - AMD Radeon HD 6990
                            Core (MHz)    Memory (MHz)
           Current Clocks :    950           1250
             Current Peak :    950           150
  Configurable Peak Range : [500-1200]     [75-1500]
                 GPU load :    99%

[ovoskeuiks]

Supa what type of card were you reflashing?

[hugolp]

Strange - maybe different manufacturers set different ranges? I'm out of options, though - given the MSI Afterburner stuff - I'd assume that it *must* be possible to go outside the configurable peak range on Linux, too. (There's a thread somewhere here - you've likely seen it - where Windows users with MSI Afterburner are finding a "sweet spot" around 300MHz; it'd be good to have that available on Linux...)

I have two Asus 5870 and the memory can go as low as 200Mhz with AMDOverdriveCtrl. The sweet spot for me is 335Mhz. But I just got a XFX 8750 and while I can get the memory to 335Mhz, it wont allow to push the core speed more than 900Mhz. It depends on the vendor.

[Folax]

I have two Asus 5870 and the memory can go as low as 200Mhz with AMDOverdriveCtrl. The sweet spot for me is 335Mhz. But I just got a XFX 8750 and while I can get the memory to 335Mhz, it wont allow to push the core speed more than 900Mhz. It depends on the vendor.

I got an Asus 5870 and an Alienware 5870 in the same LinuxCoin box.
AMDoverdriveCTRL allows me to:
Asus: 300-1200GPU 200-1200MEM
Alien: 300-900GPU 200-1200MEM

So the Asus runs great @ 1000//335
The Alien runs slower @ 900//310

Would love to set the GPU of the Alien higher but cant, so my conclusion is that it really depends on the manufacturer what the rangers are on the card, and of course you should be able to alter them but for me it's been hard fining how to alter the Alien.

[hugolp]

I have two Asus 5870 and the memory can go as low as 200Mhz with AMDOverdriveCtrl. The sweet spot for me is 335Mhz. But I just got a XFX 8750 and while I can get the memory to 335Mhz, it wont allow to push the core speed more than 900Mhz. It depends on the vendor.

I got an Asus 5870 and an Alienware 5870 in the same LinuxCoin box.
AMDoverdriveCTRL allows me to:
Asus: 300-1200GPU 200-1200MEM
Alien: 300-900GPU 200-1200MEM

So the Asus runs great @ 1000//335
The Alien runs slower @ 900//310

Would love to set the GPU of the Alien higher but cant, so my conclusion is that it really depends on the manufacturer what the rangers are on the card, and of course you should be able to alter them but for me it's been hard fining how to alter the Alien.

I just solved it this morning. I used SBE and winbios (or something like that) to get the bios from the Asus, copy the limitations, then mix the limitations of the ASUS with the bios of the XFX and reflashing the XFX. Works like a charm.

[Folax]

Is there a guide somewhere on how to do this and where to get the installation packages?
When I do a forum search on SBE I get a lot of (German) BTC betting stuff but nothing on this tool, also 'Winbios' does not return much unfortunately (only this post).

[hugolp]

Is there a guide somewhere on how to do this and where to get the installation packages?
When I do a forum search on SBE I get a lot of (German) BTC betting stuff but nothing on this tool, also 'Winbios' does not return much unfortunately (only this post).

It was RBE: http://www.techpowerup.com/rbe/ Just follow the official tutorial, its all explained.

[coblee]

Try atitweak: http://forum.bitcoin.org/index.php?topic=25750.0
This new tools works much better for me.

[kirax]

I've got 6950s and 6970s.

RBE warns on certain changes that the native drivers may stop recognizing the card.. and someone else mentioned after a certain RBE edit even aticonfig wouldn't find the cards.

Are you using a signed 'rbe' excerpt from another card (~1kb) to get around that?

I cannot for certain say for those, but I am running 6870's, with RBE modified bioses. The newest version, 1.28, supported overvolting them, which is pretty useful. The doom and gloom forum posts about the cards not being recognized in windows and BSOD's seem to be limited to the windows world. I used "method 2" , aka the no checksum, direct write, screw it lets see if it works method, to increase my overdrive limits to 1200 MHZ on a couple of cards so far, and linux has been happily mining away now for days on them as I test for stable clocks.

Note, I changed the GPU register, modified the fan curve, and used method 2 to increase the max overdrive, but I didn't mss with any powerplay states, so I don't know if that will work or not.

Underclocking memory would likely mean modifying the powerplay states, and I have been too lazy to do that thus far.

There was a post I made about this on the techpowerup forums, but it is gone to the nether since apparently putting a hosting company in your .sig is a bannable offence. Not that I am bitter.