It really pissed me off!

- I have a silent gfx card with dual dvi (non-gamer me)
- power supply with fans but very quiet
- thermaltake cpu cooler (nice and quiet as well)
+ regularly clean the fan + powersupply fan !!!
- never had other fans in my casing, don't see the need
- quiet samsung hdd (250 gb)

I think key factors are a quiet hdd, clean fans, quiet gfx card (passive here)

I am shure i could get it even quieter but i did't have to go to any crazy expenses to get like it is now.