Linux+HD5830: Underclocking below aticonfig limit without BIOS flashing?

[xor]

Hi,
is there a way of downclocking a HD5830's memory below the limit of 900Mhz of aticonfig?
Someone told me this is possible on Windows so I'm assuming that it should theoretically also be possible on Linux.
I'm on Ubuntu 11.04 64bit with the properitary ATI drivers of the Ubuntu repository (the ones you can install with jockey) & Stream SDK 2.1

Thanks

[supa]

Get AMDOverDriveCtrl and see if it will let you go below the floor set by default.

In my experience, on 5830s and 5870s, it will allow you to set a memory clock as low as 150.  No flashing, etc, required.

[hugolp]

Get AMDOverDriveCtrl and see if it will let you go below the floor set by default.

In my experience, on 5830s and 5870s, it will allow you to set a memory clock as low as 150.  No flashing, etc, required.

Do you know how to measure the consumption of the cards in Linux? I tried radeonvolt, but it does not work on my 5870 card.

[xor]

Get AMDOverDriveCtrl and see if it will let you go below the floor set by default.

In my experience, on 5830s and 5870s, it will allow you to set a memory clock as low as 150.  No flashing, etc, required.

Works! Memory now running at 300Mhz which decreased the temperature quite a few degrees and allowed me to slow down the fan.
Also the fan-control by specifying a speed graph is a nice feature of it.
Very nice, thanks.

Doesn't allow to overclock above 875MHz though - this is the default limit of the amdcontrol tool. Is there also a way to overclock beyond that without flashing the BIOS? 

[supa]

Get AMDOverDriveCtrl and see if it will let you go below the floor set by default.

In my experience, on 5830s and 5870s, it will allow you to set a memory clock as low as 150.  No flashing, etc, required.

Do you know how to measure the consumption of the cards in Linux? I tried radeonvolt, but it does not work on my 5870 card.

I'm not sure what you mean...?  AMDOverDriveCtrl will show you the current voltage, but it won't show you any sort of power consumption or separate voltages for GPU and Memory.

Get AMDOverDriveCtrl and see if it will let you go below the floor set by default.

In my experience, on 5830s and 5870s, it will allow you to set a memory clock as low as 150.  No flashing, etc, required.

Works! Memory now running at 300Mhz which decreased the temperature quite a few degrees and allowed me to slow down the fan.
Also the fan-control by specifying a speed graph is a nice feature of it.
Very nice, thanks.

Doesn't allow to overclock above 875MHz though - this is the default limit of the amdcontrol tool. Is there also a way to overclock beyond that without flashing the BIOS? 

Whatever is reported back from the card as the ceiling is what AMDOverDriveCtrl uses, I think.  You'll need to flash to go higher.

[hugolp]

I'm not sure what you mean...?  AMDOverDriveCtrl will show you the current voltage, but it won't show you any sort of power consumption or separate voltages for GPU and Memory.

Yes, AMDOverdriveCtrl lets you see an set the voltage, but to know the consumpton of a card (and anything) you need the voltage and the current. I know some linux tools show the current and the rest of the temperature sensors. I would like to access that information in linux.