Cant Run with 4gb, also cant install KB929777

Hello, I just got a new machine.

I have 4gb of ram (2 dual channel cossair 2gbs).

Whats happen is, my computer wont load up Vista 64bit if I have all 4gb of
ram in. The problem is it works fine with 2gb and Ive downloaded the KB929777
update, but vista wont let me install it with only 2gb Ram (says it doesn
apply to my system) but the thing is I can even get into Vista to install the
update with the whole 4gb installed, it just goes to the blue screen of death
with the dump memory thing then restarts.

I can get into vista in safe mode, which shows all 4gb of ram, but in safe
mode it wont let me run th update either.

Im back to using 2gb again after I tried everything I know.

Any ideas on how to get the update installed and or Vista working properly
with 4gb RAM???

Thanks