techPowerUp posted a review on the X-Spice Kira CS 530W Power Supply

Even though X-Spice is not a very well known brand name, they achieved what nobody else could do: building an extremely quiet power supply that is stable and affordable. We are testing the 530W model today and found that it could easily handle a Quad CrossFireX rig, and produced less fan noise under load than most other power supplies in idle.

X-Spice Kira CS 530W Power Supply Review