So a few weeks ago I recieved a request for a fully-passive Home Theater PC build in a glossy black HUMBLE ITX case. The requirements regarding the hardware were not that demanding: the machine should be able to play 4k Losless REMUXes of Blu-ray movies at 60fps or more without a hiccup.
These specifications pretty much demanded a use of a dedicated graphic cards to help with the data stream decoding that simple CPUs of the previous generations could not handle. I could have gone with a Ryzen APU but the budget was tight and the person already got a GT 1030 that he wanted me to use in the build. And also the card has HDMI 2 for 4k60fps that most motherboards lack today.
After reading the request I already knew how I want to go with this one and the plan came together as follows: At first get a low powered CPU that I can easily cool with a beefy tower cooler without a fan attached to it. Secondly beefy tower cooler means no room for the power supply and since the build needed to be full-passive I could not use one anyway. Pico PSU it is then! And finally removing the cooler from the GT 1030 and try to run it passively without undervolting.
The Skylake platform seemed more then adequate for these requirements as it is dated enough to be relatively cheap but this generation already has some serious power handling enchantments that previous generations simply did not have yet. So I picked up one of the lowest-end ITX board I could find, the Asus H110I-Plus. This chipset does nothing fancy, the only requirement towards it is to house a Pentium G4500. This CPU has only 51W maximum TDP while beeing a 2 core chip and having a 3.5GHz base clock. It is powerful enough for a seemless web browsing/movie watching/office tasks and some light indie gaming as well.
The power supply of choice in my case was a low price chinese Pico PSU. It is only capable of 120Watts continuous power handling but after doing the math I realised that I do not need more. Running the test setup on the desk though i quickly found out that this little PSU is running very hot even in idle. So some modding was in order. Cut some old leftover chipset cooler to size and attached them to the PSU’s VRMs and resistors with thermal compound glue. Thermals became much better on the tiny beast and i believe it gave some headroom to the unit as well.
The CPU cooler of choice was Scythe’s Grand Kama Cross 2. This cooler is awesome! The 8 heatpipes and the upward fins on them help dissipate heat passively with the laws of thermodynamics. As this cooler can handle well over 100W TDP, I was cretain that it can handle a 51W CPU passively. And it does! Also, it is a perfect fit in the HUMBLE as you will see on the shots later.
The assembly went perfectly fine, although I wanted to cover up the PSU slot on the backplate. This gave me the opportunity to model a new part for HUMBLE to specifcally be used with a Pico PSU or even a HDPlex type unit where an external adaptor is required. This new part has the same venting cut outs as the rest of the side panels and even has a 8mm diameter hole for the connector to fit in. As it is a 3d printed part, the size of the connector can be larger and the hole can be widened with a drill.
Needless to say the PC has no issues with any type of Blu-rays. Rips, remuxes, HEVC or Youtube streams even with 96fps are smooth as butter while the graphics card is running without any fan attached and not thermal-throttling at all. Right now the PC is virtually silent. The only moving part in the whole build is the 750GB HDD that gets used as the download drive. The OS is on a SSD.
I finished up the build with an experimental wooden front panel. I used standoffs instead of the regular screws on while fixing the original fornt panel and then added the wood on that. I made some holes for the standoffs to fit in and used counterhead screws form the other side to fix the wood front panel. This time it is a simple sheet of plywood but as it looks beautiful I want to try some hardwood and maybe bamboo too.
Overall this is a pretty neat build with a really happy customer and I can not wait to get into something new with HUMBLE again!
Motherboard: ASUS H110I-PLUS
Processor: Intel® Pentium® Processor G4500
Memory: Advantech 8GB (2x4GB) DDR4 2133MHz D73960-0009
Power Supply: PICO BOX Z2-ATX-120 + 12V 150W adapter
CPU Cooler: Scythe Grand Kama Cross 2 SCKC-3000 No-fan
Case Fan: –
System drive: PNY CS900 120GB SATA3 SSD
Storage: Seagate Momentus 750GB 5000C500461A6212
Graphipcs Card: MSI Aero ITX GeForce GT 1030 2GB GDDR5 64bit PCIe without fan
Below you can find the shots of the build process.