Silent PC project

I'm looking for silent PC parts for totally noiseless desktop computer. I will use this PC for software development. This PC need to be silent, fast and video card need to drives 2 monitor over 2 DVI port. I will use 4 monitor with an additional video card in the far future.

Noisy parts are power-supply, CPU cooler, fans and HDDs. Video card need to has passive cooling with 2 DVI.

Configuration

My new PC configuration will contain follow parts:

• ASRock Motherboard with Intel P45 chipset (I haven't known yet which one). I think this motherboards have the best price/performance.
• Intel Core 2 Duo E8500 processor (best price/performance let see this benchmark result or let see the full benchmark) in the most case this 45nm CPU defeats most of costly Core 2 Quad.
• Sapphire ATI HD-3450 video card with passive thermal solution (totally silent), 512MB DDR2 RAM, 2 DVI output and TV-out. This card is also available in low-profile version. Very cheap and good for programming, browsing.

And the winners are...

• Power-supply (14 dBA):
  SilenX IXR-55-142 550W
• CPU cooler (14 dBA):
  NH-U9B (7.9 - 17.6 dBA), but we can change out fan with SilenX IXP-64-14T 92x92x25mm thermistor fan (6 - 14 dBA depend on CPU therm). This fan is innovative. If original Noctua fan with Ultra-Low-Noise-Adaptor is enough strong for holds therm low, I will not change to SilenX thermistor fan.
• Fans (max. 11dBA):
  If need I will use SilenX fans. These quiet fans have ideal performance.
• HDD (max. 20dBA):
  I will use Samsung notebook HDD (noise level: 17-21 dBA). SSD is very costly but perfect solution the notebook hdd slower than normal HDD but more quiet.

This is just a plan, to be continue... :)

If you know quieter parts, please comment it.