The wombat does not give up.. rofl @ you...
"I think I found the cause of the lag effect in 3D viewports.
Since I saw that it was not 3dsmax related only, but also in vue app., I began to think that something was wrong with windows and the mouse.
And I really think now that it is the cause."http://www.evga.com/forums/tm.aspx?m=1199957&mpage=1&print=true
What mouse are you using?