Temps, Noise, and Final Thoughts
Thermals and Noise
With Windows 8.1 installed I began testing the thermal performance of the enclosure, beginning with HD playback. While temperatures did rise with both Blu-ray and file-based 1080P video, it should be noted that the noise levels did not increase until I forced a couple of worst-case scenarios by using Prime95 and Unigine Heaven benchmarks to stress the system.
I was able to push the Pentium G3258 (Anniversary Edition) CPU to a maximum of 52.6 over ambient (with a 67 F room this was a measured temp of 72 C using RealTemp). However, the much more realistic load temperature was 35.1 C over ambient (54 C on the hottest core as measured).
Next we look at noise levels, performed using a digital sound pressure meter at a distance of 18". Ambient noise in the room was 35.6 dB.
With the ventilated design of the enclosure noise levels will be primarily component dependent. The PHT HSF was very quiet under normal use, but both the CPU cooler and included 60mm chassis fan became noticably loud during stress testing. The 60mm fan was particularly noticable, with a high-pitched sound signature. In the real world noise levels would probably never come close to what I was able to produce here, however.
Essentially, all enclosures are about compromise. Even a cost-no-object build is going to have the side effect of (typically) larger size and high energy usage. If that is not of concern for the end user, then for them it truly is a “no compromise” result. However, when the primary considerations are small size and silent operation (crucial for an HTPC build) then the tradeoffs become more problematic. For instance for the thinnest enclosures there are significant tradeoffs in CPU cooling due to height and often width limitations of the enclosure. Intel has created a blower style cooler for the thin mini-ITX platform, but not every enclosure will have the lateral room required for the Intel design.
There are more differences with the thin mini-ITX standard, beginning with memory support. Unlike regular mini-ITX which accepts standard DIMMs, with thin mini-ITX only notebook SoDIMMs are supported. Additionally, there is no x16 PCI Express slot on a thin mini-ITX motherboard. Some have a x4 slot, but upgrading the graphics will necessitate a processor swap. Though it’s possible that some sort of x16 to x4 adapter could be implemented, powering it would be a problem since we aren't using a conventional PSU with this form-factor. And here we arrive at one of the biggest issues facing the first-time thin mini-ITX builder: the power supply.
The thin mini-ITX standard calls for an external power supply, essentially a notebook power adapter. (Naturally some boards complicate this by offering an internal power header, but most rely on the Intel external standard.) Unfortunately, this adapter will not be included in the box with your mini-ITX motherboard. I have seen it included with enclosures, but if it is not included it requires very careful selection at this point to track one down. Why? The specifications are extremely, well, specific.
This is the 90W power supply I used with this build
It’s not just a 19V laptop adapter with at least 90W of power, but the tip of the adapter needs to have a 7.4mm outer diameter with a 5.0 inner diameter. If this was simply a standard, and a quick search on Amazon for “thin mini itx power supply” achieved a good result, this wouldn’t be an issue. (At time of writing the search "19V 7.4mm" produced a good result on Amazon, and the adapter I found is around $10.) Hopefully by the time you read this adapters will be searchable as "thin mini-ITX PSU", and not by plug diameter. Perfect Home Theater does offer one on their site at time of purchase, which adds $50 to the total cost.
- Excellent construction, beautiful fit and finish
- Premium feel with lightweight aluminum throughout
- Effective use of interior space
- Well ventilated
- Extremely slim design only permits thin mini-ITX form-factor
- Minimal CPU cooling options available with 23mm height limit
Overall the Perfect Home Theater ultra low-profile HTPC enclosure is an impressive and attractive addition to the living room PC market. It is expensive at $200, but this is in keeping with the higher cost of producing a custom enclosure entirely from aluminum. The width allows for seamless matching with existing components, and the design adds minimal height to any AV stack. The tradeoffs with such a low profile design might make this enclosure impractical for many, but if you are looking for a very slim case (or are ready to embrace Intel's thin mini-ITX form-factor) I would look no further.