I'm going to be running:

Core i3-2100 w/integrated video & 8GB DDR3-1333 (~40 watts idle, 80 watts load)

3Ware 9650-8ML (max 25 watts)

5x Hitachi 5k3000 2TB Drives (around 20 watts idle, 30 watts load)

So I think it will be around 85 watts idle, 135 watts load.

I will be running Hyper-V with one virtual machine, and maybe up to 3 VMs, but no real heavy load. So both PSUs should give me a TON of headroom with this config, and

**I'm basically interested in which one is going to be more efficient under idle and load. If there are any better PSU options in the US, please let me know.**

I think the Fortron Aurum Gold 400 will be the more efficient one at idle and load, but please check my calculations and let me know if they look good or not:

Fortron Aurum:

85 Watt output requires 97.7 Watt input (assumes 87% efficiency)

135 Watt output requires 153 Watt input (assumes 88% efficiency)

Seasonic ss-300et:

85 Watt output requires 102.4 Watt input (assumes 83% efficiency)

135 Watt output requires 159.76 Watt input (assumes 84.5% efficiency)

I just guessed at the efficiency %, using the official certfication levels as a guideline, but they should be close.

**So in both cases the Fortron appears better. Am I right? Have I done my math correctly?**The price difference doesn't matter a whole lot to me between these two PSUs.

I would love a Gold or Platinum option in the 250-300 watt range, but the only ones I've seen mentioned anywhere are the Fortron FSP250-60EGA, and the HuntKey HK400-52PP, neither of which look like they are in the US.