Vista + Platform Update + DX11 SDK + 8800 = no CS4.0 cap bit

I have the following:

8800 GTS
195.xx Beta Driver
August 2009 D3D SDK
Vista with october “platform update” and all service packs.

I can run DX11 examples, as long as they have downlevel 10 code in HW acceleration mode, however, the “CS” samples that use CS4.0 always fall back to Refrast.

Digging a bit further: The DX Caps viewer reports “Compute - Optional (no)”

The 195 driver release notes explicitly state that the 8800 would have Compute shader support. I also had 185, which also supposedly had this.

On another machine with a 260GTX, Windows 7 RC1, and the SDK, it reports “Compute - Optional (yes)”, and samples like NbodyCS run flawlessly in hardware. It reports CS4.0 capability.

So is there a specific check for vista/W7 that might still exist in the driver? I’ll be getting windows 7 soon, but I was hoping to get this working now on my vista machine (since the rest of dx11 seems to work). It would also be handy for Nvidia to create a chart of what card has what caps on for each OS, if it’s the case there are differences, for dx11.

There is a registry key in the Vista drivers which disables CS by default. In Windows 7 it’s enabled by default.

After deleting the registry key, it works in Vista aswell. It’s mentioned in the release notes of the GPU Computing SDK.

I’m not sure why it is disabled in Vista though, and I suppose that once the driver goes out of beta, it will be enabled by default.

I happen to have an 8800GTS myself (the original G80 model with 320 mb), and I can tell you from personal experience that it will work in Vista.

Thanks for letting me know this works, however, I’ve read about 10 different release notes, from driver 186 to the present 195s, to the CUDA SDK (2.3), and walked through every nvidia related registry key using regedit, and I’m still unable to find any mention of this special key anywhere, Could you just post what registry key it is please?

I am in a similar situation. Please indicate the registry key required.

After quite a bit of searching, I found the answer:

http://developer.download.nvidia.com/compu…lease_Notes.txt

snip

1. After download the driver, run the Driver Installation installation, this

   may require a reboot of your system.
   

   2. Remove the registry key from the Windows System registry

      Open the registry editor in the window

      Start → regedit

      Click at the very top icon labeled “Computer” in the Registry Editor

      Search for D3D_39482904 the string. If found, delete it from the registry.

      There should be about 2 instances of this registry key

end snip