Powering an x4 from a Mondo: how many mA can I get?

[maxolotl]

I have a voodoo mondo. I got an X4 to expand it.
I'm trying to figure out if I'm getting enough milliamps to the x4 to run all my stuff.

The mondo has 400mA outputs that can deliver either 12v or 9v.
The X4 has a 12v input.
All the pedals I'm plugging into the X4 take 9v.

Since 400mA at 12v is 4.8 watts, and 4.8 watts at 9v is 533.33mA, does that mean that by using two 12v 400mA outputs on the mondo to power the X4, I can draw a total of 1000mA from the X4 and be OK?

Or is there something I'm missing?

[Rez]

Voltage conversion as such is not doable with 100% efficiency, thus...

If you power the X4 from the two 12V 400mA outputs combined (with a Current Doubler Adapter, part# PPAP), the 9V outputs of the X4 will have a maximum total output capacity of 800mA.

Hope this helps!