looks good to me. But that is way more PSU than you need for a HTPC with integrated graphics. On the otherhand, if you ever decide to add a discrete graphics card for gaming, you'll have the wattage to run it. Likewise with the motherboard. A bit more than necessary for integrated video; 2 PCIe slots? No, you don't need SLI.
Loudness is in the ear of the beholder. It won't be dead silent with 3 120MM case fans, a PSU fan, and the CPU's fan running. But Silverstone is a good name and they say 'quiet fans', so it may be OK.
Btw, You will need an optical drive to install the operating system and you may want to watch DVDs.
Ah, so the PSU is more than necessary...
But as you said, it's possible that I may add gaming at a later date, so I think I'll leave that as it is.
As for the optical drive, I got an old one that I'll just use to install OS.
And I watch videos either through Netflix or with external HD so I won't really need to spend $$ on a new one.
Thanks for the help clutchc.
Geekapproved, will that PSU allow me to attach a video card later?
Sounds like you have a fun build ahead of you. I built a similar HTPC awhile back for myself. But with less CPU and PSU. Great little machine. But a 40" HDTV from my easy chair about 12' away was hard to see when web surfing. I had to downscale to 720p to read the text.
You mentined not needing a keyboard/mouse. Wireless?