After playing around with PD8 on my new desktop, I finally managed to understand the minimum requirements to produce 1080 video in a comfortable manner.

You really do need a quad core no matter what! mine is 2.33GHz and the CPU processes at almost 75% when producing my video

Editing multiple videos sources tends to make PD8 freeze up momentarily when trying to view the entire timeline in Movie mode. This also happens in Clip mode also when I try to view certain clips also.

The amount of RAM required is about 3GB from what i see (RAM usage was about 1.8GB When producing)

All this was using my example footage which was 1080i and 1080p with very few corrections to the raw footage. the clip was about 3-4 minutes and took around 4-5 minutes to produce.

http://www.youtube.com/watch?v=5kp43-xDtp0

My current setup is:
Intel Core 2 Quad Q8200 2.33GHz
4GB DDR2 RAM PC6400
200GB Hard Drive (IDE) this could be the problem...
Radeon HD4650 512DDR2 GPU