Help with new HTPC build ?

ok, so here is the jist of the hardware im gonna use
http://www.antec.com/Believe_it/product.php?id=MjUwNg==
Antec ISK 100 [case]
http://uk.gigabyte.com/products/product-page.aspx?pi...
Gigabyte E350 [motherboard]
hard drive will be a SSD made by OCZ its in my house dont know exact made model but its a 60gb drive
not planning on putting an optical drive in (dont even think it would fit box anyway lol)
oh and a single stick of 4gb DDR3 1333 (unbranded)
so the case has a 90W power supply provided, on my checks i seem to find this will be plenty to run all the hardware on idle or full load - its planned use will be HTPC
ie playing movies/tv shows streamed from internal network or some simple surfing or youtube'ing for catchup tv and the like - not sure if will have any games but if yes then it will be simply low res ones

i was about to start ordering when i happened to look at the gigabyte page for the board and at the bottom of the specs it say 200W min for this board

WHAT

a mini-itx board designed for HTPC's (i suspect) and they say it'll be needing 200W
anyone care to let me know if i will hit a problem running the whole setup using the 90W supply or will i actually need the 200W the board claims it needs?

help please.......

If all you are using is the board, RAM and an SSD then 90W will probably be fine. It almost certainly won't be fine if you added the 3 other SATA devices and graphics card and then hooked up 8 bus powered USB devices that the board could support.

thats what i thought
as you say - plan is just for memory, ssd and board itself, granted there will be an external usb connection but it would either be powered external drive or things like keyboard/mouse or some wireless media player remote control type thing
only other connection i can think would be usb charging for mobiles (galaxy s2 not any apple products)