Originally posted by: RedStar
i think this will make it clearer to you:
http://www.extremetech.com/article2/0,1697,1982033,00.asp
"ExtremeTech: Speaking to that point, we know that the desktop in Vista is drawn using DirectX 9. What happens if you have a DirectX 10 card? Does the desktop still use DX9, or does that switch over and use DX10?
Blythe: It continues to use DirectX 9. Largely the reason for that is when we built the desktop, that was being done concurrently with the design of DirectX 10. It becomes somewhat more complicated to build both the low-level technology and the thing on top of it, concurrently. It's better to sort of have a time gap between those. At the same time, we were making some minor tweaks to DirectX 9 to accommodate new features that were needed to do the desktop. For us, it's best to have one consistent platform. Even though we could imagine there being benefit to the desktop using DX10, it's better to do all the debugging and get it to work with DX9 and ship that. Then over time, as the hardware base builds up for DX10, by the time we do the next major release, we'd be looking at trying to move the entire desktop onto 10
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