Anyone can confirm if the above coolers will block the PCI-E slot in Gigabyte GA-H77N-WiFi Miin ITX board?

FYI, Antec reply the DC-ATX board of this case support up to 100W power brick.

Sorry for a stupid question, how can I install OS to the hard drive of this motherboard without a SATA DVD drive?

I have a 90W brick which is left behind from a Dell Inspiron 8600, however, it output 19.5V instead of 19V, don't know if it suitable for use, or I can just give it a test.

Thanks for the detailed explanation. Dose it make any sense to change a 90W power adapter or it won't make any different without upgrade the DC/DC power board inside? I assume my configuration below should be safe to use with the stock Antec ISK 300-65? Zotac GeForce 9300-ITX WiFi Celeron E3200 2.40...

I have a question how could a 65W power adapter power up a motherboard with CPU alone already 65W+?