Motherboards with fanless cpu - kaby lake?

msxyz

Newcomer
I am looking for a Micro Atx motherboard with a fanless, onboard cpu for a silent htpc. All those I found, however, are using a cpu based on the atom architecture (braswell or the slightly newer goldmont variant), which are 6-10w tdp processors with 2-4 cores; each core is a pretty basic dual issue in order cpu.

Having recently assembled an htpc for a friend with a Pentium N3700 (four core braswell, 2.4 Ghz) I've a good idea of what these cpus are capable of. They're not bad cpus but a bit limited for anything than old games (with an external video card) and media playing.

Among Skylake and the newer Kabylake CPUs, there are some low power variants for tablets and embedded systems with a TDP of 7.5-15w. These cpus are found in some tablet PCs and in set top boxes, but I cannot find a standalone motherboard for assembling a small silent pc around it. I'd like to avoid using a 35w CPU, which would require a more sophisticate (or noisy) cooling solution, but it seems I've no choice.

Before giving up, as a last resort, I ask here if somebody knows of a mATX or ITX motherboard with a Core Y / U low power processor and eventually a full length PCIe slot for an external video card.
 
What about a duct and pull design for the cpu cooling potentially allowing for a higher CFM silent fan at the back?
 
I'm exactly trying to avoid to complicate things up. One large (18cm) fan spinning at low rpm (600-900) and cooling all the interior is okay, but since space and money for the project are limited, the components must be able to be cooled effectively with small, passive heat sinks.

I'm a bit baffled by the void between low power, low performance solutions available either in mATX or ITX form (Atom, Puma or Carrizo-L based, all sub<10W) and standard, small motherboards with a socket to mount the usual 35W+ CPU. A 15W CPU would fit just fine and it will have enough processing power even for modern games, paired to an external video card (small form factor too, passively cooled or with a backup fan that kicks in only above a certain GPU temperature).
 
Are we talking about a HTPC or a living room gaming pc? Because if its just a HTPC (consuming media) you can buy a fanless NUC or something similar. Better yet, buy the new Nvidia shield tv and install Plex/Emby on a NAS/server. That way you can also easily use Netflix, Amazon prime etc.

If you want something a bit more high performance then the question because how about the other parts? Fanless PSU? Fanless GPU? Fanless case? etc.

If you buy a big heat sink and a low RPM fan I'm pretty sure its going to be inaudible when idling/watching movies. During gaming there is a lot bigger chance you're going to hear your gpu fans because every half decent GPU produces a lot more heat than the average CPU.

And even if you passively cool the cpu and gpu, as soon as you want to extract any reasonable amount of performance from them you're going to need casefans to keep things from overheating. In that case you're better off running low RPM casefans and a CPU cooler instead of a passive cpu and high rpm casefans because you'll need a lot more airflow to keep it cool.

I looked into something similar last year and came to the conclusion that a fanless/silent htpc with reasonable performance has terrible cost/performance.

Much better options are:
A) Go with something like a Shield TV and have the media server somewhere else (broom closest or whatever).
B) Pull a HDMI and USB cable from wherever you got your pc to your living room. That way you can easily switch between your monitor and tv. Buy a Xbox controller and you can boot into steam from your sofa, from there you can also boot into Kodi or whatever your HTPC front end is and control it with the controller or buy a bluetooth remote.
 
I'd like a media pc, to keep near the tv, that can also play the occasional game at decent detail. As I travel a lot for work, I happen to play often in my spare time on laptops, so I've a good idea of what it possible to do with 40-50W of power budget. To some gamers playing on medium-high settings at 'only' 30 fps may sound too much of a compromise, but for me it would be ok.

Today, I spent some time again looking for motherboards with embedded CPUs but with little success. Excluding Bay Trail, Braswell, Goldmonts CPU, the sole motherboard close to my idea is this:
http://www.gigabyte.com/Motherboard/GA-C1037UN-EU-rev-10#ov but... WTF? They implemented a PCI slot instead of a PCIe?!? Another alternative would be a server motherboard with a low power Xeon but these start at 350-400€ and only a few of them come with full size PCIe slots.

Since Braswell motherboards come very cheap, I may try again to assemble a small PC around a Pentium N3700 CPU paired with a good (i.e. GTX1060) video card and see what happens. At worst, I'll have wasted some time.
 
Seen the IDE slot on that GA-C1037UN-EU ?
This mobo is some years old (Ivy Bridge) and they probably didn't think someone would want to make a gaming PC with a mobile Celeron. Back then PCI still was more versatile : tuner card, inexpensive 100Mb ethernet card, sound card, serial ports card or any legacy/weird purpose for the slot.
This board served a ton of purposes : low end desktop, ITX desktop, revive an old PC while reusing everything down to the IDE drives, firewall, server, industrial..

CPU power is for retrogaming unless you choose your games really carefully.. So why use something other than the integrated graphics?

Since Braswell motherboards come very cheap, I may try again to assemble a small PC around a Pentium N3700 CPU paired with a good (i.e. GTX1060) video card and see what happens. At worst, I'll have wasted some time.

Seems like a way to play vid games from about 2005/2006 on a 4K 60Hz TV at native resolution :)
(if one really wants to do that.. that makes the 1060 3GB version good for something)

One solution could be AMD Bristol Ridge APU, soldered (FP4) 15 watt variants, see there :

http://wccftech.com/amd-bristol-ridge-fp4-family-leak/

But that requires playing the waiting game again.
Why not a regular motherboard and kaby lake Pentium? Then go into BIOS settings and turn it into a low wattage CPU by yourself. Lots of freedom to lower the clock multiplier and voltages. APU for AM4 motherboards (Bristol Ridge again) might be decent, of note will be the ITX motherboards without chipset (X300 and A300)
 
Last edited:
I'd like a media pc, to keep near the tv, that can also play the occasional game at decent detail. As I travel a lot for work, I happen to play often in my spare time on laptops, so I've a good idea of what it possible to do with 40-50W of power budget. To some gamers playing on medium-high settings at 'only' 30 fps may sound too much of a compromise, but for me it would be ok.

Today, I spent some time again looking for motherboards with embedded CPUs but with little success. Excluding Bay Trail, Braswell, Goldmonts CPU, the sole motherboard close to my idea is this:
http://www.gigabyte.com/Motherboard/GA-C1037UN-EU-rev-10#ov but... WTF? They implemented a PCI slot instead of a PCIe?!? Another alternative would be a server motherboard with a low power Xeon but these start at 350-400€ and only a few of them come with full size PCIe slots.

Since Braswell motherboards come very cheap, I may try again to assemble a small PC around a Pentium N3700 CPU paired with a good (i.e. GTX1060) video card and see what happens. At worst, I'll have wasted some time.

If you want to play games at decent detail wouldn't that automatically mean a actively cooled GPU?

I think you'll be better off with a system cooled with low RPM fans to make it (almost) inaudible rather then trying to go all passive.

Alternatively you could also go the Nvidia Shield TV way, if you have a pc with a Nvidia GPU that can stream games to the Shield.
 
Yeah, passively cooling a CPU and most other components isn't too difficult. Passively cooling a decent GPU is going to be an issue. That said, it shouldn't be too difficult to passively cool a GTX 1050 or maybe a Rx460, as long as your system is laid out in a way to facilitate good passive cooling. Finding a good passive cooler for those cards might be more problematic. It's been a few years since I've looked into passively cooled video cards that would offer a somewhat decent gaming experience.

If it's meant for the living room, you can always locate the HTPC in another room. That's what I do as my HTPC doubles as my home server as well which requires active cooling for my installation (multiple mechanical HDDs) I have a 15 foot HDMI cable to the TV, and shorter USB cable to a powered USB hub that brings the RF receivers into the living room to get a better signal from things like the keyboard, mouse, game controller, etc.

Regards,
SB
 
@Phamra: sure, they all employ Atom cores... Every major manufacturer has them. It's incredible how articulated is the offering while consumption and features are more or less the same.

@Blazkowicz: I've a Lenovo laptop with a FX8800P (on of the few with true dual channel mode) and it's a solid performer. I was able to successfully undervolt it, so it never throttles down and stays cool (<60 deg) even during gaming. The CPU side is a bit more powerful than a Core Duo of similar frequency (incredible how far behind AMD fell in these last few years), the GPU is a GCN 1.3 generation and quite efficient, despite being bandwidth starved. I can play most games up to 2011-2012 at fullHD resolution without problems. The FX8800P is a 36W CPU however (with 45W peaks unless, as I did, it's undervolted from 1.32 to 1.2 - It takes a bit of luck because not all CPU may reliably work at reduced voltage)

An ASROCK N3700 motherboard is underway. I used the same before for building a friend's HTPC and it's a nice little motherboard. BIOS let's you run all the four cores at 2.4GHz at the same time, so it 'cheats' a bit with the turbo mode. It has a full size PCIe slot (only 1x - 500GT/s though - that's the same bandwidth of the good old AGP slot that debuted 20 years ago!). For the videocard, I've picked an EVGA GTX1060 Superclocked. Half length card with copper dissipator, heatpipes and 'silent mode' fan that doesn't kick in till the GPU reaches 60°. I don't think the CPU will crunch enough numbers to stress that card, so there is a chance the fan will stay off. I've not chosen a case yet. I'll be re-using a spare Silverstone SG10 with a 180mm, low speed fan and a SIlverstone 300W fanless PSU. I like that tiny case and it's my favorite when I want to try some board; due to its excellent accessibility, I can quickly assemble a working PC in less than 10 minutes.
 
You're pairing a GTX 1060 with an Atom CPU using a PCIe 1x bus?

AFAIK there are plenty of passive GTX 1050 cards out there, and even those would be awfully bottlenecked by the Atom cores.
 
I know, I've a spare Ti750 that would probably do just fine. I have bought the GTX1060 with the intention of using it later on my gaming rig; by using a very fast GPU I can have a better idea of the CPU bottleneck/slowdowns. Once the test is over I will either:
1) Follow Tongue_of_colicab advice and give up with the silly projects :D
2) Do something stupid like buying an expensive, mATX or mITX server motherboard. :runaway:

BTW, I found another desktop motherboard with the Celeron 1037U: http://www.biostar.com.tw/app/en/mb/introduction.php?S_ID=654 This one has a proper PCIe interface and a small fan ontop of the CPU; a slightly larger cooler would probably render the fan useless, since the CPU has 15W TDP. Still no signs of similar motherboards using haswell/broadwell/skylake low power Celerons and that's a damn shame. Last year i bought for my wife an Acer Chromebook with a Celeron 5005U that would probably be perfect for the PC I've in mind.
 
The problem is that you want both small and fanless, and that's hard to get on a DIY x86 setup.

Practically speaking, you could get a mini-ITX motherboard with a 35W CPU, slap some cheap heatsink and use it in a smallish mini-ITX case with only the case's fan working connected to the CPU fan in the motherboard.
I bet the case's 120mm fan could not even kick in most of the time.
 
This is an "Atom" yet again, ditto the quad core version.
The first one above does have the PCIe 16x slot @ 2x ; CPUs have four PCIe lanes built-in
But quad cores motherboards linked to so far have PCIe 16x slot @ 1x (spending a lane or two on PCIe 1x slots or mini PCIe slot)
ah ok, they're just not using the Atom nomer anymore, labelling them all Celerons now.
 
The new Atoms (14nm) are labelled Celeron when they're artificially limited or have some execution units disabled and Pentium when the full core is made available.

Motherboard is on the way, so I'll have the whole weekend to play with it, but I reckon the best solution would be to buy a socket 1151 motherboard and put a low power Core or Xeon (25W OEM versions are available on eBay) with a passive cooler and a single large, low speed fan on the chassis blowing air on the CPU and VRMs. Of course, the BOM goes up because such a solution would easily cost 2-3x as much as a motherboard with an embedded CPU.
 
Back
Top