tiny voices :
there is not limit to the ammount of storage a motherboard can support. That isn't how it works. It will be fine.
Thanks for the quick reply
I forgot to mention i planned to boot the htpc from the 4TB i.e win 7 would be installed.
I just went through the online manual again and i found this
"Support bootable HDD over than 2TB UEFI breaks the limitation of 2TB bootable HDD on traditional BIOS. With UEFI, you can enjoy the bootable HDD size over than 2TB!" so hopefully it should work