Windows driver to disable discreet Radeon card?

I have an old HP Pavilion laptop with an i7-2720QM CPU and Radeon 6770M discreet GPU. As far as I can tell, the latter is broken at the hardware level: Fedora Linux tells me that it is not responding and Windows 7 refuses to boot with the hybrid graphics driver that I've always used. I've worked around this by removing all traces of Catalyst from Windows and installing Intel's HD Graphics driver, but this seems to leave the 6770M drawing as much power as it can. When I'm in Windows, the laptop gets pretty hot and the fan never shuts down.

This doesn't happen in Linux (which takes an extra 20 seconds to boot, but eventually tells me that it is going to ignore the discreet card) so I suspect that despite the broken hardware, there must be a way to stop it from drawing power. Does anyone know of a driver or a trick that does this? I've checked the BIOS and there's no way to disable it from there. I've also tried to disable it from the Device Manager, but that does nothing.

 

If you don't have the same problem under Linux, the card is not completely broken. PCIe doesn't have a physical switch to turn something off. The host can only send the device a command and hope that the devices will enter a low-power mode on its own. So if your card is cool under Linux it's still responding to the host in some way.

As for how to cool it under Windows, you can try playing with PCIe Link State Power Management settings, but without a working driver I'm not sure if you'll get any response.

 

Do you have any bios options to disable it?

 

Thanks! Indeed, the card is not fully dead: GPU-Z can see it in Windows (although most of the parameters reported are nonsense) and Linux will occasionally skip the extra 20 seconds during boot, although when it does this, the machine inevitably freezes soon after boot. I will look into PCIe Link State Power Management.

LTBonham, there is nothing in the BIOS except the option choose between dynamic and fixed GPU switching. I tried this, but it does nothing.

 

So I tried to set the PCIe settings in the Windows power management to maximum power savings for both battery and plugged in. This doesn't appear to have done anything for Windows, but Linux no longer goes through its 20 seconds of telling me that it the device is not responding which is nice. Since the two operating systems shouldn't be aware of each other, I suspect this is yet another case of HP modifying BIOS settings via Windows. I really wish they'd just let me do it in the BIOS...

Since the card now appears to work properly (or at least not complain) in Linux, I figured that I might be able to reinstall the hybrid driver which I've always used, but no dice -- it's still broken in Windows. Oh well, at least Linux boots faster now.