help describe the problem 7.5.3 does not open a lot of vst

does not open a lot of VST 3 vst 64bit

People help to describe my problem, those support Cubase .
the Bali ’ full version Cubase 7.5.30 64bit plugins also use 64Bit and then begin problemy use VST3 waves of RAM I 16 GB processor Intel core i-73960@3.30 . in short many resources, but I peristat otkryvaetsja plugins, culbuto triggered some kind of limitation, it is on the 64bit plug-ins, the video is visible.
32bit plugins opened without restrictions, but if you use them a lot then the cube often westnet, ishetoo I little practical

uad to the problem is not involved in the problem in vst 64bit

I got enough resources on my PC (16 Gb RAM, Intel Core i-73960@3.30) but I get limits when I try open some more plugins in VST 64 bit. Is that because Cubase x64 have some limits for plugins quantity? I counted 63max.(format vst3 64bit)
If not so what I need to do?