well, this is tricky...
my friend Beer40 just build a new HTPC with that same motherbaord
and he cant power on his htpc from a total off state using his MCE remote pachage...
it just doesnt work for him,,,
its a hit an miss kinda thing..
u may try the remote package suggested by r1lee,
if it worked for him, well, maybe it'll work for you but,.
im just saying its not %100...
but if it ends up working,
then, u can use lets a harmony remote with your receiver.
it'll work..
in return, visit his htpc thread, good infos there
http://forum.xbmc.org/showthread.php?tid=128009
specially
Unisen's iPazzPort Mini RF 2.4GH Keyboard (KP-810-10-A) Turns on you pc from cold with this mobo.