Thanks for reply. Good point about the DirectX version showing as 10. The DirectX Diagnostic Tool is showing version 11 on my PC on the first page but DDI 10.1 on the second page (see screen shots)??
I am running Windows 7 Pro retail. THE ATI drivers are the latest released mid Oct.
I can't find a WEI screenshot anywhere for a Radeon 5850 to confirm what DirectX version they are showing.
I did find another person with the same query here:
Low WEI score with Radeon 5850 - Hardware Canucks
I don't want to hijack this thread if this is a technical issue so let me know if I should go somewhere else in the forums.
1.) Are you running 64-bit?
2.) Have you downloaded the latest DirectX End-User Runtime (9/16/2009)?
3.) Is your PCI-E bus 2.0 and running at 16 lanes? (Check with GPU-Z)
4.) Have you tried some game benchmarks?
Thanks for the repy. To answer the questions, yes, yes, yes, not yet.
However I have identified the reason

and here is the reason in case others find themselves asking the same question.
The ATI 3D control panel has a slider between performance and quality. Any setting between Optimal Performance and High Quality gives a score of 7.7. Optimal Quality (furthest right - this is what I was using) gives 6.0. I am note sure what changes but something is causing the hit. I am going to play a few legacy games to see if they are affected as I am guessing something (AA maybe) is being enabled for everything not just when a game asks for it.
My old nVidia 880GTS did not exhibit this behaviour with all the setting on high.
The DirectX reporting is a red-herring, although it does beg the question, is it a reporting bug or is Windows 7 Aero actually using athe DirextX10 API?
Attached is my new WEI with ATI High Quality setting (the Q6600 is o/c to 3.0GHz).