"limitations of OPUS 150W dc/dc" i bet it makes **** coffee and won't be much company on a lonely winters night.
It should run that i think but we need more specs.
ie what pci cards
what hard drives and how many
same for optical drives
your question is a bit too vague. Have a look at some other systems on here, a few people with hight power are considering dual opus or you might have to power your drives from another seconday psu e.g. a 90W one. There is a power calc outhere somewhere and there will be a link to it if you search (i aint finding it for you i spend far too long on this forum) but i suspect your cpu will draw somewhere between 60-80watts alone. There is an Opus 200w coming out and that should be fine.