Greegor wrote:
http://www.amd.com/US/PRODUCTS/NOTEB...450-specs.aspx

This DIRECTX 11 card has DRIVERS for WinXP and W7.

If the DIRECTX 11 hardware and firmware can't
be used in WinXP then what does the driver
do with it?

Would a game application actually prefer
DIRECTX 9 hardware/firmware to the
DirectX 9.0c software module?

I see a card that has shaders and stuff for DIRECTX9.
Would the DirectX 9.0c software module USE that stuff?

http://www.amd.com/us/products/deskt...fications.aspx

I found when studying upgrade options that
back when the upper CPU chips were $500
or $600 each, upgrading seemed less worthwhile
but now those same chips are $10 to $30
like the high end ones with hw Virtualization.

When a CPU that used to go for $600 sells
for $30, upgrading isn't so far fetched.

"Certified drivers for Windows 7, Windows Vista, and Windows XP"

Presumably, not the same driver. The driver would work with
things usable by the target OS.

If it didn't support DirectX 9, there'd be no point listing
a Windows XP driver.

Using another card as an example...

http://www.amd.com/us/press-releases...2009sep22.aspx

"superior performance in the latest DirectX 11 games, as well as in
DirectX 9, DirectX 10, DirectX 10.1 and OpenGL titles"

I don't know if I can come up with a search term specific
enough to find a table with that information in it.

WinXP uses an XDDM driver, while the later OSes have some
flavor of WDDM driver.

Notice they do mention backward compatibility so that
WDDM can support older titles.

http://en.wikipedia.org/wiki/WDDM

"The WDDM specification requires at least Direct3D 9-capable video card
and the display driver must implement the device driver interfaces for
the Direct3D 9Ex runtime in order to run legacy Direct3D applications;
it may optionally implement runtime interfaces for Direct3D 10/10.1
and higher."

But the driver for WinXP would be XDDM. It means it is quite possible
the hardware has to support more than one variation in its interface.
It also means, you could run into a video device, that no longer
has support for XDDM. While WDDM has some backward compatibility
defined for it, there's nothing to say ATI/NVidia have to support
XDDM forever on new designs. They could drop it at any time,
simultaneous with stopping WinXP driver support.

(Ref here)
http://download.microsoft.com/downlo...GuideWin7.docx

Paul