I'm looking for silent graphics for $135 and I narrowed down my decision to these two : SAPPHIRE AMD Radeon HD6670 1024MB DDR5 Ultimate PowerColor Radeon HD6750 Eco there is also Gigabyte (but noticable electronic noise) and Asus (weak on inputs and power) can you tell me something more about electr...

I'd need something good to cool i3570k; which one is better Mugen 2 rev. B or Noctua NH-U12P (first rev) ?