Looking for an external power supply for mini itx, HTPC External Power

Im trying to find ( and failing epicly ) an external power supply unit for my htpc build, my build specifications are listed below. I do not have my motherboard or tv tunner yet as the motherboard will be released in Mid November. I need to find an external psu something like the picture posted which is a PicoPSU-150-XT ( which is a 150 watt psu ) but I want to make sure that 150 will be enough for my application, All the 200 watt internal connectors are too big for my case so if I need more than 150 watt I will have to get an internal psu. UNLESS someone knows of some that looks like the picture only in a 200 watt. Really I even wonder if I could just get away with using the picopsu-150 watt power adater, as I have no clue as to what the wattage usages are between my components or how many watts an atom n330 motherboard even uses.

ANY HELP WILL BE GREATLY APPRECIATED !

Operating System - WINDOWS 7 Ultimate
Case - Lian Li PC-Q07 Mini-ITX Case
HDD - Western Digital WD500AAKS ( 500GB x 1 )
Ram - Corsair 800mhz CM2X1024-6400C4 ( 2GB x 2 )
Optical Drive - 5.25 Full Size HD-DVD / BLU-RAY Drive ( Sata connected )
TV Tunner - Hauppauge WinTV-HVR-2250 Dual TV Tuner ( PCI-Express x1 )
Motherboard - ZOTAC IONITX-G-E ( 1.6 GHZ Dual Core Atom N330 )

Motherboard specs can be found at the link below :
http://www.zotacusa.com/zotac-ioni [...] board.html

PicoPSU specs can be found at the following link :
http://www.mini-box.com/picoPSU-15 [...] 8Ta38Qahf0

There is an internal psu extender mount available for my case at the link below:
http://www.lian-li.com/v2/en/produ [...] dex=84&g=f

That would be true if you didnt look at the board inforfmation at the link i posted, the board I choose has BOTH, a mini pci meant for wifi, AND a regular PCI-E x 1