Log The no-compromise APU HTPC: Brickless, semi-fanless Ryzen 5 4650G in a Lazer3D HT5 [updated: 09/2021]

[Valantar]

Edit: updated first post with new text and pics; original post is in a spoiler tag below.

I seem to be kind of allergic to finishing my build logs. Oh well, I finally got around to installing the new custom top panel on this PC, and the overall impression after using it for nearly a year is that it is fantastic. I mean, really, really good. The cooler has performed impeccably, running passively for essentially all usage of the PC. The fan stays off even in many gaming workloads, or turns on intermittently. The APU also performs fantastically, with the CPU part being significantly overpowered, and the GPU doing its job great. I played a decent amount of Ori and the Will of the Wisps at 1080p medium settings, and it ran at ~75fps consistently. That game in HDR on a good TV also looks fantastic.

Here are some updatd shots with the new custom top plate. It's in matte rather than gloss acrylic, and rather than a huge circular cut-out it has an enlarged version of the stock HT5 vent slots, sized to be larger than a stock 140mm fan for extra space for passive airflow, plus mounting holes for the fan.

While the PC did look great previously, IMO this new top plate just makes it perfect. I could have countersunk the fan mounting screws if I really wanted perfection, but they don't bother me, and I'd rather avoid drilling into the acrylic. 5mm acrylic doesn't crack as easily as thicker stuff (and this is good quality acrylic too), but I'd still rather not risk it. Also, if you're interested in any custom panels for a Lazer3D case, Kevin is incredibly helpful, and prices are great.

The PSU solution has worked flawlessly. The only thing that is slightly imperfect is that the RPS-200-12C whines a tad when the system is asleep and off - but it's only audible close by and when paying attention. It's perfectly silent while the system is running. It has also been 100% stable, and does not seem to give off noticeable heat. I ought to get the shell of the PSU painted black so it isn't quite so visible from outside of the case, but again, I'm not that much of a perfectionist.

Other things worthy of note: the heatsink got mangled quite a bit in order to fit it over the ArchDaemon and RAM. Yes, the RAM is in between the fins. RAM sticks are covered in kapton tape on the top to protect them from scratches and any electrical connection to the heatsink.

It was worth it for the clearance though. Here's the final fitment:

I also made a dump of a bunch of photos from the build process. There's pics from the construction of the heatsink, my work on the case (including cutting a new power inlet, which I'm extremely pleased with how cleanly I pulled off), plus how the old top panel looked when installed.

Spoiler: Original post

Just to push myself to actually make a proper build log for this build, here's a little teaser for my HTPC build. I've been working on it for a little while now, finally got my cooler assembled and - kind of shocking, really - it works really well. Huge thanks to @aquelito for help getting my AM4 mounting bracket laser cut. I haven't yet got it into the case, and I'll likely have to trim some fins to get the PSU (MeanWell RPS-200-12C) to fit, seeing how the fins overlap both sides of the motherboard. Shold be fine though. Height to the top of the fin stack from the box the motherboard is sitting on is ~57mm. I haven't torture tested the cooler completely passively, but it did make it through a few minutes of OCCT (AVX) all-core load not that far above 80C, just slightly dropping below 4GHz. I've set the fan to kick in at 60C, which means that in a quick test game (offline) of Rocket League, the fan was turning off while gaming That freaking shocked me. I mean, RL isn't the heaviest load, but it's at least a 100% GPU load with some CPU load thrown in.

Some teaser images:

Now, let me tell you, sandwiching five layers of aluminium together around a cold plate with heatpipes through it takes a lot of thermal paste. And my rather off-the-cuff design for the mount (only really measured the cold plate, only partially accounted for the heatpipes) needed quite a bit of cutting, filing and other work. Also had to sand down the base layer by ~.3mm to get it flush(ish) to the copper cold plate. And did I mention I had to cut away a few fins to fit my DC-ATX board?

Full specs:
CPU: Ryzen 5 Pro 4650G (CPU stock, iGPU 2100MHz, IF 1900MHz)
RAM: Crucial Ballistix Sport LT 3200C16 @ 3800C16
Motherboard: ASRock B550M-ITX/AC
Cooler: Arctic Accelero S1 (possibly rev. 2?) GPU cooler from ~2009 with a similarly old Noctua NF-A14 FLX
PSU: AC-DC is a MeanWell RPS-200-12C, DC-ATX is @guryhwa's ArchDaemon (200W spec, only DC input and EPS connector)


Some notes on Renoir OC'ing:
- Hitting 3800 MT/s on my RAM was trivial. Taiphoon Burner for info, Ryzen DRAM calc for timings, booted first time (3800 safe preset @ 1.38V). Would likely go significantly higher if the calculator let me try that.
- Setting IF to 1900 was similarly a non-issue, just needed to do it manually as on auto it stopped at 1800.
- The iGPU OC was also pretty easy, but I couldn't get it stable above 2100 without using voltages that I'm not comfortable with. (The voltage readings from this motherboard are scary, reporting 1.3-1.4V on both CPU and SoC/iGPU). Nearly all voltages at stock, SoC set to 1.15V.
- Performance uplift from stock + XMP to my current setup is nearly 18% in 3DMark Night Raid.


More to come, obviously.

 

[BaK]

Nice, will follow closely as I've also started a 12V APU build, but with the older/cheaper 3400G.

Why such a choice of CPU cooler? Just because you had the Accelero at hand?

 

[Valantar]

Nice, will follow closely as I've also started a 12V APU build, but with the older/cheaper 3400G.

Why such a choice of CPU cooler? Just because you had the Accelero at hand?

Thanks! I'm very happy with both the MW unit and the ArchDaemon. My MW has a slight hissing noise (transformer I would guess), but it's not really audible from a distance, I doubt I'll hear it when it's in the case. Besides tweaking the output voltage slightly (it started at 12.08V according to my multimeter, but a slight adjustment on the output voltage wheel got that down to 12V flat) and crimping the cables it was essentially plug-and-play.

As for the cooler: Pretty much, yes. I had it around, plus the fan, and wanted to see if I could make use of them. The Accelero is kind of annoying as a GPU cooler as it's quite tall, so using it for a CPU cooler seemed like a decent fit. Plus it's freakin' huge compared to most LP coolers, but has much less dense fins, making it better suited for (semi-)passive cooling. Also, while something like an NH-L12S or Big Shuriken 3 would probably have cooled this just as well (or likely better with the fan running), I kind of wanted to re-use something rather than just go the easy route and buy everything new. The DIY challenge was obviously also a motivator.

 

[BaK]

I was wondering if it was because you had planned to OC so much that you needed a powerful cooler!
Recycling and DIY sound good, especially if it gives you the opportunity to learn something. This sandwiching job looks indeed not that easy! Good job on it!

 

[Valantar]

I was wondering if it was because you had planned to OC so much that you needed a powerful cooler!
Recycling and DIY sound good, especially if it gives you the opportunity to learn something. This sandwiching job looks indeed not that easy! Good job on it!

Thanks The HT5 is (thankfully) big enough to fit reasonably powerful coolers like the Noctua L12S and Scythe Big Shuriken 3, so I could probably have gotten better overall cooling under high thermal loads with one of those, but I don't think either of those would do well if I switched off the fans thanks to their dense fin stacks. So it's a bit of a trade-off overall, but given the main usage for this PC will be media playback I'm hoping it can run completely fanless for that (well, 4k60 video might make the fan kick in I guess), and I don't think either of those other coolers would have handled that. And of course as the thread title says I didn't want compromises, I want to be able to play some games too, and thankfully it seems to handle that equally well. I haven't tested the APU under anything more strenuous than Rocket League yet, but its performance so far has definitely impressed me.

I also wanted to test this out as more of a design principle - I like the idea of a flat, semi-passive cooler with a much larger area than something like the Black Ridge or IS-47K/IS-60, though of course I understand the challenges this raises in terms of motherboard and case compatibility. Most people aren't willing to cut the ends off the fins of their cooler to make it fit their case

To be honest though, I'm kind of surprised it worked. I was hoping it would work, but I'm by no means an engineer or product designer, so I was halfway prepared to go order a new cooler. But it did! Which to me makes this whole build just that much more fun - I can say for certain that my HTPC is unique And I've come to learn that I have a preference for a rather specific kind of DIY SFF PC projects - starting off with something that's kind of cheap, old or otherwise imperfect, but then putting enough time and effort (and in this case, money, at least compared to just buying a $50 cooler) into it to make it work really well - that's definitely the case for my modded Optiplex, and while this is a very different build (mostly new parts, for one), it kind of fits the same overall theme.

 

[Valantar]

Sigh.

I guess that's what I get for hoping that my "this seems a bit too tall" measurements were in fact fine, rather than being thorough the first time around. Time to remove the heatsink, bend it down some more, bend and snip some more fins to ensure it clears the RAM, and try again. 7mm or so is a bit much, but i believe it's doable. I could always get a slim 140mm fan instead... but I don't want to

Also had to ditch my filtered AC input, as the fan hit it. Kind of expected, but that means I have to solder the input wires as i don't have crimp plugs that fit my unfiltered C14 sockets. Considering cutting a hole for the AC input on the PCIe side of the motherboard instead. Decisions, decisions...

 

[BaK]

Good luck with the 7mm adjustements!

Also had to ditch my filtered AC input, as the fan hit it. Kind of expected, but that means I have to solder the input wires as i don't have crimp plugs that fit my unfiltered C14 sockets. Considering cutting a hole for the AC input on the PCIe side of the motherboard instead. Decisions, decisions...

What is that filtered AC input? Is it a must have when dealing with 12V / Mean Well PSUs?

 

[Valantar]

Good luck with the 7mm adjustements!


What is that filtered AC input? Is it a must have when dealing with 12V / Mean Well PSUs?

It's not a must, more of a nice-to-have. All ATX PSUs (and ones based off electrically compatible standards) of decent quality have some sort of input filtering, which essentially serves to minimise input noise and fluctuations from the AC signal. You can buy AC input receptacles with this filtering built in, such as this (that's literally the first result when searching for "Filtered C14" on Mouser, not an endorsement ). How necessary this is depends largely on the quality of power where you live - if there are large voltage fluctuations etc. it's definitely good to have.

 

[BaK]

Thanx for the explanations, got me interested in adding one to my build now!

 

[aquelito]

Finally !

You should get a Prolimatech slim 140 mm fan : these things move a lot of air and are pretty silent (unless you place them at less than 5 mm from the ventilation holes panel).

 

[Valantar]

Finally !

You should get a Prolimatech slim 140 mm fan : these things move a lot of air and are pretty silent (unless you place them at less than 5 mm from the ventilation holes panel).

Thanks! It was really about time that I got around to building this, though I mainly blame the delay on AMD for not putting out retail desktop Renoir. You're probably right that I should get a slim fan, but then I would need to change the title of the thread to "The no some compromise APU HTPC", which I don't want to In all honesty though, I'll probably go that route if I can't squeeze it down by the required amount, but I want to give it a try first. We'll see over the weekend what I can manage. Vent turbulence shouldn't be an issue: I've got two top plates for the HT5, one of them has a circular cut-out for a 140mm fan with a wire grille, so turbulence should be nearly nonexistent, though with a slim fan even the stock slitted one might work too.

I'm also a bit miffed at just how shiny those top plates are - I really should have ordered those in matte black like the rest of the case. Guess I might give them a light wet sanding for more of a frosted effect, though of course I have no idea how that will look on dark semi-translucent plastic.

 

[BaK]

It's not a must, more of a nice-to-have. All ATX PSUs (and ones based off electrically compatible standards) of decent quality have some sort of input filtering, which essentially serves to minimise input noise and fluctuations from the AC signal.

Sorry to ask again about this, but doesn't the RPS 200 already have such input filtering built in?

 

[Valantar]

Sorry to ask again about this, but doesn't the RPS 200 already have such input filtering built in?

You're right about that, but given the size of the PSU and the space requirements for good input filtering in ATX and SFX PSUs I more or less assumed that what's in the MW is significantly less effective. I'm no electrical engineer, so I frankly have no idea if that's right, but I don't see the harm in doubling up on filtering like this (and PSU reviews do seem to follow the logic of more filtering = more betterer). I've seen a few builds using these filtered inputs too, and they're not particularly expensive, so I essentially thought I'd rather be safe than sorry. But as I said above, unless your AC is really noisy, it's a nice-to-have, not a necessity.

I really need to find the time to write up this build log. Build has been finished and in service as a HTPC for about a week now, working fantastically. Just ordered a new top panel with a different design from Lazer3D though, as I'm not happy with my current (also custom, so I can only blame myself!) one. Still, doing a build like this, perhaps with a more sensible cooler unless you like going to weird extremes, is highly recommended.

 

[Valantar]

Self-necro: updated the original post with new pics, description and experiences, plus a photo-dump of the build process. Really loving this PC!

 

[BaK]

Thanks for the update!

Here are some updatd shots with the new custom top plate. It's in matte rather than gloss acrylic, and rather than a huge circular cut-out it has an enlarged version of the stock HT5 vent slots, sized to be larger than a stock 140mm fan for extra space for passive airflow, plus mounting holes for the fan.

This new top panel looks really nice!
Makes it a very stylish piece of hardware with the wood on front!

The PSU solution has worked flawlessly. The only thing that is slightly imperfect is that the RPS-200-12C whines a tad when the system is asleep and off - but it's only audible close by and when paying attention. It's perfectly silent while the system is running.

I'm also in the process of building an HTPC, but with a MW RPS-500-12C PSU (build log to come very soon). I am not hearing any whine noise from my PSU, however I am running it without an AC filter. Maybe what you hear comes from the latter! J/k

Good job on cutting the heatsink to make it fit around the PDCB, PSU and RAM!

Other things worthy of note: the heatsink got mangled quite a bit in order to fit it over the ArchDaemon and RAM. Yes, the RAM is in between the fins. RAM sticks are covered in kapton tape on the top to protect them from scratches and any electrical connection to the heatsink.

RAM sticks in between fins, that's definitely the SFF spirit!


Don't you mind sharing how you 'communicate' with your APU from the couch?
Like how do you deal with launching games, movies or browse the web?

One option I see so far is putting Win10 in tablet mode, which will let me select a game or a video player from the Windows tiles easily with a wireless gamepad.
An other option would be to have Kodi on autostart, and lauch both movies and games from there still with a gamepad. The 'Advanced Emulator Launcher' addon seems to be able to start any games.
But as browsing internet pages requires a keyboard input anyway, I might as well get a remote-mouse/keyboard along with games or video player shortcuts on a regular Win10 desktop.

 

[Valantar]

Thanks for the update!


This new top panel looks really nice!
Makes it a very stylish piece of hardware with the wood on front!

Thanks! I'm really happy with it. As I said, I just took the original design, expanded the vent pattern+added the fan mount holes, and sent the drawing it to Kevin for laser cutting. He deserves a lot of credit for both taking on the extra work + making sure it came out perfect. That matte black acrylic is absolutely fantastic - I wish I had ordered the top like that to begin with

I'm also in the process of building an HTPC, but with a MW RPS-500-12C PSU (build log to come very soon). I am not hearing any whine noise from my PSU, however I am running it without an AC filter. Maybe what you hear comes from the latter! J/k

Oh, that sounds very cool. I'll have to keep an eye out. Good to hear you're not hearing any whine - I think I just got unlucky (it was like that back when I test ran the PSU with some very janky AC wiring, so it's unrelated to the filter ). Definitely not audible from the couch or anywhere else one is likely to sit with the PC off - I'd say I need my head less than 1m away and the room to be quiet to notice at all.

Good job on cutting the heatsink to make it fit around the PDCB, PSU and RAM!

RAM sticks in between fins, that's definitely the SFF spirit!

Thanks! Yes, I was quite happy with that. Took some convincing with various tools to shuffle them sufficiently to the side to fit the RAM in between, but it worked very well. And I'm glad my mangled heatsink is appreciated I'm frankly surprised at how much of a beating those heatpipes could take without leaking. I think if I ever were to design a case it would be an APU case with a bundled semi-passive cooler somewhat like this (though compatibility would of course be a challenge) - though ideally with a bit better finish quality than this

Don't you mind sharing how you 'communicate' with your APU from the couch?
Like how do you deal with launching games, movies or browse the web?

One option I see so far is putting Win10 in tablet mode, which will let me select a game or a video player from the Windows tiles easily with a wireless gamepad.
An other option would be to have Kodi on autostart, and lauch both movies and games from there still with a gamepad. The 'Advanced Emulator Launcher' addon seems to be able to start any games.
But as browsing internet pages requires a keyboard input anyway, I might as well get a remote-mouse/keyboard along with games or video player shortcuts on a regular Win10 desktop.

We're pretty old school in that regard - just a small BT keyboard and wireless mouse (specifically, the MS Wedge keyboard + Logitech M330 Silent Plus). Anything more "living room oriented" just turns out janky in my experience, and keyboards with trackpads tend to be too large, really crap quality, or both. It's also rather difficult to find media remotes etc. with Nordic/Norwegian ISO keyboard layouts. There's also an Xbox controller with the wireless dongle for gaming+headphones. This + 150% scaling on the UI works out well on our 55" TV (at ~3m viewing distance). I guess it helps that there's just two of us, and we're both reasonably familiar with using a PC.

 

[BaK]

We're pretty old school in that regard - just a small BT keyboard and wireless mouse (specifically, the MS Wedge keyboard + Logitech M330 Silent Plus). Anything more "living room oriented" just turns out janky in my experience, and keyboards with trackpads tend to be too large, really crap quality, or both.

I'm quite happy with the following air mouse/keyboard I have on my old HTPC.
I was not expecting much for such a low price but it does the job quite well!

7.11US $ 31% OFF|C120 Fly Air Mouse Wireless Game Keyboard Rechargeable 2.4Ghz Keyboard Remote Controller for Smart Tv Mini PC Android|Remote Controls| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

It's also rather difficult to find media remotes etc. with Nordic/Norwegian ISO keyboard layouts.

I don't know how much you need to type specific nordic characters, but setting the keyboard layout as english let you actually type what is labeled on the keys! Easy enough for some URLs to type on some web searches.
But if you also need to write longer sentences (or SFF posts ; ), I guess you are more comfortable on a 'real' keyboard.

 

[Valantar]

I'm quite happy with the following air mouse/keyboard I have on my old HTPC.
I was not expecting much for such a low price but it does the job quite well!

7.11US $ 31% OFF|C120 Fly Air Mouse Wireless Game Keyboard Rechargeable 2.4Ghz Keyboard Remote Controller for Smart Tv Mini PC Android|Remote Controls| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

I don't know how much you need to type specific nordic characters, but setting the keyboard layout as english let you actually type what is labeled on the keys! Easy enough for some URLs to type on some web searches.
But if you also need to write longer sentences (or SFF posts ; ), I guess you are more comfortable on a 'real' keyboard.

Wow, that is cheap! But sadly that layout would be a no-go - it's even reduced width, with O and P being moved next to the spacebar, while I'd need extra keys for Æ, Ø and Å, which are all pretty frequently used in Norwegian. Something like that would probably do okay for entering urls and stuff as you say, but if we'd need to keep a proper keyboard close at hand for anything else that would just be more hassle than it's worth.