My case is not low profile and I don't care about passive cooling. Minor fan noise does not bother me.
I'm not certain I will overclock the CPU, and even if I do, it will be a moderate overclock (to 3.8 GHz at most). I might even undervolt if I can do it while getting the performance I want (I managed to OC and undervolt the Sandy Bridge in my main PC). This system will not have any HDDs, optical drives, or any PCI/PCI-E (other than video) cards. It does have a SSD and 4 (non-LED) fans. I would think a 400W power supply should have no problem handing that load with up to a 7850 card (~100W max for the card, ~100W max for the CPU).
I'm not certain I will overclock the CPU, and even if I do, it will be a moderate overclock (to 3.8 GHz at most). I might even undervolt if I can do it while getting the performance I want (I managed to OC and undervolt the Sandy Bridge in my main PC). This system will not have any HDDs, optical drives, or any PCI/PCI-E (other than video) cards. It does have a SSD and 4 (non-LED) fans. I would think a 400W power supply should have no problem handing that load with up to a 7850 card (~100W max for the card, ~100W max for the CPU).