Inventor 2012 downgraded its graphics?

[acfang]

Hello,

I am having a problem with Inventor 2012 running under boot camp (Windows 7) on my 2011 Mac Mini. Please pay attention to the order I did things:

1) When I first installed inventor, it worked fine and the graphics were nice and responsive. 

2) Then I installed Parallels 7 on the mac side to try out inventor there.  It didn't work nearly as well. 

3) I went back to Windows 7 boot camp to reconfirm that it worked well, and indeed it did.  At that time, I had this under the hardware diagnostics:

AIRViz Device Manager \ VirtualDeviceDx11
Feature Level 4_5
Performance Mode
Hardware Renderer

(other info snipped)

Graphics driver log information:

(...)

Dec/01/2011-18:32:00:    Reset to D3D11 factory: D3D9 -> D3D11.

4) I went back to the Mac side / Parallels and tweaked the settings around (switched from Performance to compatibility) until things seemed to be working only slightly slower, but with a mouse lag.  In that environment, I got a log as follows (sorry, this was when it was in performance mode, not compatiblity):

AIRViz Device Manager \ VirtualDeviceDx9
Feature Level 3_1
Performance Mode
Hardware Renderer

(other stuff snipped regarding using the Parallels driver)

Graphics driver log information:

(...)

Dec/02/2011-02:40:13:    Fail to create D3D11 factory, We need to change it for current inventor session: D3D11 -> D3D9.
  Failed to create a device from the adapter.

5) OK, HERE IS THE BIG PROBLEM.  After a while, I decided to go back to the windows (boot camp) side, but now the performance was no better than on the mac side.  Switching the graphics setting back and forth didn't seem to help.  I now have this for the hardware diagnostics:

AIRViz Device Manager \ VirtualDeviceDx10
Feature Level 4_0
Performance Mode
Hardware Renderer

(...)

Dec/02/2011-16:25:06:    Fail to create D3D11 factory, We need to change it for current inventor session: D3D11 -> D3D10.

So in short, from all the switching back and forth, something got messed up and now inventor falls back to D3D10 and less hardware acceleration.  How can I switch it back to original or somehow get it to re-detect?

[acfang]

UPDATE:

Doing a repair installation of inventor didn't help.  I just ended up re-writing back an older image I had of the partition.  Now Inventor is back to using the DX11 4_5 mode.

Shrug.