Reducing Power Usage

[Chronictank]

Hi i did some searching but i cant seem to find the answer i am looking for,

I am trying to find a way of reducing the power usage of my card when the system is idle, I have a 3870X2 and using the AMD GPU Clock tool i found that one of the cores always seem to be running at a fast speed.

Core0:
Idle:
GPU: 823.00 Memory: 900 Temp: 74oC
In Use:
GPU: 823.00 Memory: 900 Temp: 79oC

Now i looked at the other core and it seems to be set at a much lower clock

Core1:
Idle:
GPU: 297.00 Memory: 900 Temp: 44oC
In Use:
GPU: 823.00 Memory: 900 Temp: 54oC

Is there any way i can set both cores to be run at the lower speed when on the desktop and a higher speed when the gpu is needed, ideally automatically? I was under the impression the card automatically clocked to 2d mode when in desktop for this very reason
I am running vista so aero may be the cause of this, but surely all 800+ mhz isnt required to run aero

will setting a lower speed manually cause problems?
I also am wondering if this will make any difference as surely the voltage wont change?

 

[Chronictank]

When i am playing games i don't really care how much power the system uses as it comes with the territory, a highly clocked machine is inevitably going to use a lot of juice.

However having a core running at full pelt when it is idle is just wastage i am trying to reduce

 

[Chronictank]

I don't know if ati tray tools supports the 3870 x2 or not, but assuming it does you could just create a custom profile with low clocks and voltage for general desktop use.

it probably does but vista doesnt play nice

The only way to reduce Power/heat is with a bios editor and reduce the Voltage in the 2D settings .

I thought as much :/