[KJReisman]

I'm brand new to XBMC, but having set it up on my desktop and playing around, I have to tip my hat to all the developers. Nice work!
I got inspired to build an HTPC after having horrible streaming performance over the Xbox 360 from movies stored on my wife's desktop PC. (The problem is the PC, my gigabit network is pretty fast.)
I also want to be able to play a wider format of files, video chat over the big screen, browse the web from the couch, some light gaming, better slideshows, more customization, Hulu etc. I also tire of my family seeing movie titles on the Xbox but not having an easy, immediate way to see what the movie is about. We're also looking at moving the Xbox to another room.

I will be connecting via HDMI to a Sony 5.1 AV Receiver, connected to a 55" Vizio 1080p 120Hz LED. The electronic shelves in the TV Stand are not well ventilated, and aesthetically I can't put even a mini-tower PC in the room. However there are two open shelves on either side of the TV stand which are open on three sides (the Xbox is on one, as it was getting too hot in the inside shelves. The spaces are 12" wide by 6.5" high and 22" deep, so I figured a mini-ITX system might fit in there just right.

So here's what I'm thinking, trying to keep the price under $500:

OS: Windows 8 64-bit ($0, thanks father-in-law!)

Motherboard: ASRock FM2A75M-ITX - http://www.asrock.com/mb/AMD/FM2A75M-ITX/index.us.asp ($95)

CPU: AMD A8-5500 Trinity 3.2GHz (3.7GHz Turbo) Socket FM2 65W Quad-Core Desktop APU (CPU + GPU) with DirectX 11 Graphic AMD Radeon HD 7560DITX ($105)

Case: Either the Apex MI-008 (with 250W PSU) or the ThermalTake Element Q (with 220W PSU) ($50-$60)

RAM: Kingston Hyper X Red 8GB DDR3-1600 (PC3-12800) CL10 Desktop Memory Module, maybe double that. ($40-$80)

HDD: WD Caviar Green 2TB 3.5" internal ($90)

Optical: LG Internal SATA DVD Writer (I have a Sony BD Player already hooked up) ($16)

120mm case fan (if needed) ($5-$10)

Remote: Either a Flirc (http://flirc.tv/) so I can use my current Universal Remote, or Rosewill RHRC Windows 7 and 8 MCE remote. ($12-$24)

Keyboard/Touchpad/Remote: KEYDEX Wireless 2.4 GHz Handheld Mini Multimedia HTPC Keyboard with Touchpad ($17)

Total: $430 - $497

[KJReisman]

My questions are, am I going too big for my needs, and do I have any compatibility issues with my components?

[fvtalon]

For compatibility you'll have to wait for someone with those cases to chime in, but as far as overkill you'll find many people on here would recommend the A6-5400k vs the A8-5500. They're both 65W TDP but it seems the A6 uses less energy and thereby should run cooler and the A6 should be lots of power for a HTPC. A8 has more CPU grunt and a GPU that's better yet tho. As to the RAM the trinity chips are also supposed to see a bit of a performance increase on the GPU side by using 1866Mhz RAM vs 1600Mhz and there again, 4GB is the usual recommendation for HTPC duties. 8GB is a common option and can't hurt when it's only a few bucks more but to go to 16GB (as I think you're suggesting) is almost certainly overkill.

I would consider a 60-64GB SSD for the OS to help speed up overall performance and boot/shutdown times. (~$70 & Crucial M4, Samsung 830 or Intel are solid choices)

[bluray]

CPU: AMD A8-5500 Trinity 3.2GHz (3.7GHz Turbo) Socket FM2 65W Quad-Core Desktop APU (CPU + GPU) with DirectX 11 Graphic AMD Radeon HD 7560DITX ($105)

A8-5500 is perfect spec for your new LED HDTV and Sony 5.1 surround sound system......it'll make great HTPC...!

[KJReisman]

Thanks.
I hadn't thought about an SSD for the OS. Now I'm thinking I should just use one of those and read all the media from my backup NAS.

[bluray]

With SSD for OS, it'll be a little bit snappier. This "Crucial M4 CT064M4SSD2 2.5" 64GB" should do the trick....