I have a directx 9.0c problem with it reporting the "Approx. total memory: n/a".
previous elements of the problem to narrow it down to directx registry settings, are detailed here:
I just loaded an old registry backup to the machine.
It caused a lot of problems, but dxdiag did report everything correctly, and the software in question worked.
loading the harddrive backup now, for fairly "clean" slate to begin the registry debug on.
I could use some help with what registry keys to look for.
I have CompareIt! v2.89 for side by side registry comparison.