Hi
I am told that Vista is missing some aspects of Direct x 9 and that installing it will install these, however, would this overwrite Directx 10, or would the install of Direct x 9 only put in the bits that are missing still leaving me with Direct x 10.

DX9 and DX10 are two different installs. One can not overwrite the other. Unless there is some kind of weird fluke.
From Chuck Walbourn Technical clarification: Windows Vista's runtime supports Direct3D9, Direct3D9Ex, Direct3D10, and older interfaces. DXDiag reports it as "version 10" for simplicity, but that number has been meaningless for a few years now. The Windows Vista runtime also supports all the other usual DirectX 9.0c interfaces except DirectPlay Voice and Direct3D Retained Mode which were removed. When you run the DirectX End-User Runtime installer or a game uses the DirectSetup REDIST on Windows Vista (or XP SP 2 for that matter) nothing in the runtime gets updated or installed. Only the SDK optional components like D3DX9, D3DX10, XACT, XINPUT, etc. get installed.
The new Aero desktop uses Direct3D9Ex. This API requires Windows Vista, a DX9 card, and a WDDM driver. It does NOT require Direct3D 10.
The Direct3D 10 API requires Windows Vista and a Direct3D 10 video card. No released game creates a Direct3D 10 device at this time, although a number of them have been announced as coming in future products and/or patches.
If you are missing any version of D3DX due to a failed or badly desigend installer, run the DirectX End-User Runtime Installer on the Microsoft site and it will install all the supporting SDK components we've released. Got to microsoft.com/directx/ and follow the link for "Get the Latest DirectX Here".

"Uncle Nobby"

I installed a program that renders some graphics in 3d, it downloaded an extra direct x 9 package and installed it along side of direct x 10...
worked great.. but of course slower than xp... since this is of course vista we are talking about.
Vista: watch the grass grow (tm)


"Uncle Nobby"

On Mon, 30 Apr 2007 23:13:00 +0100, Uncle Nobby wrote:

It's only missing one .dll from DX9 which you can download from the top of this url and drop into your system32 folder. WTF Microsoft left one file out that breaks compatibility with some older games is beyond me. Sometimes they have their head up their ass.
slitherine.com/downloads/

The file that is missing isn't for older games. Newer games such as FEAR, BF2142, Command and Conquer 3 use those files as well. The difference is, those games come with the redistributed installer and installs the files it's missing.
Here is an example of what you'll get if you try to runt eh game FEAR without running the DirectX runtime updates images.filecloud.com/431143/missing_DX_file.jpg
Granted, I am a bit puzzled on why Vista didn't include any of these updates, Since the one FEAR wants is from Aug 2005. but at the same time, they release updates every 2 months for Direct X 9 runtime and it's pretty easy to go to Microsoft.com and apply the latest update.