Vista x64 problems with 3dmax 2009 and Aero

[pentexplorer]

Sorry I know this must have been covered many many times probably..but I want to know how you deal with x64 vista with the problems I face..I read around few forums including this that aero will not work hand in hand with 3d programs and also enabling the 3d program running in xp sp2 compatibility mode and disabling desktop composition.. I did all of that and also running at dx9 with auto redraw window viewports..I cant use maxtreme since I am on 8800GTS 640mb card. but still I find the GUI pretty laggy compared to my xp 32bit. I am on 4GB ddr2667 ram and all my other applications (gaming,multi-tasking) all definitely have benefited from the 64-bit processing and 4gb but I find my 3dmax is pretty slow compared to my 32bit xp as in viewport handling and preview of materials..is there any tips and tricks you guys can share? I thought vista x64 would have been better by now already since I have heard it from last year but should I make a further investment to xp64 or up the 4GB to 6GB to notice a better difference? I havent really done thorough testing since I just got my vista x64 ultimate but would like to be pointed in some good direction in optimizing my 3dsmax for the best. Is directx10 advisable to use as well?