You should really deal with the components one by one though. The P180 Mini won't magically make a noisy PC silent, or even quiet. It should be seen as a final step to making a very quiet rig silent, or a noisy rig just a little bit quieter. Like a vacuum cleaner running in the next room, then you close your room door. The door will muffle the noise a bit, but it'll still be annoying to listen to.
I already have the P180 Mini, thanks though
* Replace the stock CPU cooler with a quiet aftermarket one.
* If that HD6570 has a tiny-whiney fan, get rid of the fan and replace it with a small but quiet case fan zip-tied to the heatsink. Or replace the graphics card with a quieter one.
* Replace the Antec TriCool (870RPM on the low setting) with a quieter 120mm fan, same goes for the other case fans if they buzz/tick/squeak/drone etc.
* PSU fan? If it's noisy, do a fan swap, or replace the PSU with a quieter one.
1: Going to buy One
2&4: Its ok for now
3: I will buy a new one, once I go to the store
Thanks For the Info guys, I have decided against the foam, but going to buy a new heatsink, and intake fan