I'm building a SFF system, and because size is an important factor for this system, I am planning to use an Antec ISK-110 case, which has a 90W PSU built in. The PSU is rated at "up to 92% efficiency." Link to case: http://www.newegg.com/Product/Produc...82E16811129185 The parts: Core i5-3570K + Gigabyte Mini-ITX Motherboard (Microcenter combo) No dedicated GPU No overclocking No optical drive 8GB 30nm Samsung DDR3 128GB Samsung 830 SSD 500GB 5400 RPM 2.5" Hard Drive (WD Scorpio Blue) No case fans, only fan in system will be the stock Intel CPU cooler I am going with the 3570K because of the Microcenter combo deal. I wouldn't really save any $ if I went with a i5-3450 or something like that, so I figured why not go for the 3570K, especially since it has the faster HD 4000 GPU. Will the 90W PSU of the ISK 110 be able to handle this setup? Will it have enough power left in reserve to plug in a USB optical drive or a USB external hard drive?