Heap Size Within Registry

Have been experiencing issues all of a sudden there is a limit on the number
of windows and tabs I can have open.

For example, while in the past I might have as many as 20 windows open, the
new limit seems to range between 9 and 16 depending upon the number of tabs
open within IE7.

The 3gb of ram with virtual settings and free hard drive space providing
additional resources should do the trick. They do not.

So Microsoft recommends changing the Desktop Heap Size (Article ID: 126962)
to xxxx,yyyy,zzz where "zzz" is 256 or 512. Well for me it already is 512.
The actualy string is ObjectDirectory=\Windows SharedSection=1024,3072,512.

Any suggestions as to whether or not I can bump the 512 number and if so, do
I need to change any other part of the string???

Thank you,
AJ