Problem med Windows 7, Sony Vegas 9 og RAM

Jeg har skrevet en mail til en gut, som beskriver mit problem ganske glimrende. Den er på engelsk, men jeg håber I forstår det:

I am desperate for help. I am experincing a problem and found this thread, where you have answered:

http://forums.creativecow.net/thread/24/897809

I am an amateur editor/film maker working for a school to produce videos and therefore they have bought me a computer to administrate and use.

The computer is a Mac Pro with the following specifications:

Processor: quad-core: One 2.66GHz or 2.93GHz Quad-Core Intel Xeon 3500 series processor (Don't really know which one)
Memory: 16GB of 1066MHz DDR3 ECC SDRAM
Graphics card: ATI Radeon HD 4870 with 512MB of GDDR
HDD: 640GB Serial ATA 3Gb/s, 7200 rpm, 16MB cache

I am running Windows 7 64 bit via Boot camp.

I have a lot of problems with Sony Vegas Pro 9.0, 64 bit. I think they are related.

1. When I edit, sometimes media bin content(not used in project yet-files) and normal preview windows turn completely black, but with sound playing. Just no picture. It happens alot and is fixable by leaving Vegas alone for some time or quitting the program/rebooting the computer.

2. When I wish to render, it is not possible. I've tried .mp4 and .avi. The error is always "System low on memory[...]".
I did manage to start a render one time and it finished, but the file only played sound and 'generated media at the end'. Nothing else.

I think it is a memory problem; I have tried changing the dynamic RAM allowance on preview to 16GB RAM, 6GB, 520MB, standard(320MB) and less. Nothing helps. I have also, as you recommend in the thread, tried to make a page file of 6GB. Did not help.

I am FRUSTRATED. I had enough problems with actually figuring out how to get Vegas on a mac in the first place and through a billion problems, I finally got Windows 7 and Vegas working... almost.