Some words about my setup with a fanless HTPC running MC18 and ROHQ.
Several months ago I decided to go for MC (and I haven't regret that). I was also determined to build a nice looking, silent HTPC. I didn't want to hear a lot of noise coming from the HTPC. Some low spinning fans could of course be accepted as my AVR (HK AVR 760) has been modified with two low spinning Nexus fans (a bit of soldering, a zener-diod solved that).
I had for a while been following the fanless chassis of HDPLEX,
http://www.hd-plex.com. Finally, the H5.S was back in stock and I could get my hands on a black one (when a chassis is out of stock, it could take some time before it's back in stock again). The H5.S is a chassis for micro ATX/mini ITX with support for a full height expansion card. It's also possible to order internal mounted IR receiver with remote.
The other parts were a i7 3770S with iGPU HD4000 (TDP 65 W), Intel 330 SSD 120 GB, 8 GB DDR3 1600 MHz and a mini-ITX ASUS H77P8-I motherboard. I had no problems in assembling the parts. Not all mini-ITX boards are compatible with fanless heatsink system. More micro ATX boards are compatible with H5.S. The ASUS H77P8-I is compatible if you're using angled SATA-connectors (you the can't use all six, but 2 and that's ok for an HTPC) below the heat pipes.
I did some tests of the fanless heatsink system. I ran some Prime95 tests and the CPU temperature wasn't above 65 °C at full load. At idle and light load the CPU temperature is about 35 °C and 40-45 °C respectively. I also tested with the stock CPU heatsink fan bundled with the 3770S and this is in fact some degrees lower than with the heatsink fan. This is impressive! The stated max TDP of 75 W for the chassis seems reasonable.
So, how does it work in running MC18 with Red October High Quality (madVR). The i7 3770S is capable of running HD (progressive) material at almost the highest settings, Bicubic 60 for chroma and Lanczos 3 with anti-ring for image (luma). For SD material you have to choose Mitchell-Netravali (or similar) for both chroma and image.
Some words also about the USB adapter in the front port. That's a USB (IR) adapter that receives IR commands from a remote control,
http://www.flirc.tv/. I didn't want to have yet another remote control in addition to the TV and AVR remote. With this I've been able to program my HK AVR 760 remote to simulate any keystroke on a keyboard. After some initial problems (the product is rather new and under development), it's now working very well and I can controll Theater view with my AVR remote.
The chassis is looking awesome in my setup and Larry at HDPLEX has been very helpful answering different questions.