Log My handheld PC projects

[CC Ricers]

Most of last year was has been kind of hectic for me, and was hoping I had more time to spend working on this build. But it's a new year now and the project's heading in a different direction.

I won't be using the Larkbox anymore. It will be replaced by the Lattepanda Delta SBC as I have found a used one at a decent price. It was more of a impulse buy but at $150 it felt too good to pass up. They're currently out of stock at the DFrobot store but Lattepanda Alpha should be back in March, so that could be a nice upgrade for the future.

Anyways, I found a build log on BitBuilt where someone else already accomplished using the LarkBox in a portable console that came out looking very good, using a 7 inch screen instead of 5 inch with mine. Here is a video of the log (again, not mine and it's in Korean):



My LP delta fits in the same footprint of a smaller 5.5" screen and doesn't require destructive modding or bodge wiring like the Larkbox does. I've realized that most of the challenge is fitting all the components in a smaller case because while most DIY builds of this kind roughly match the Nintendo Switch in size, I've been aiming more for Switch Lite size.

Here's a peek at the SBC attached to the OLED screen. The screen has mounts for a Raspberry Pi so I needed to 3D print brackets that adapt the holes to the Lattepanda.

While using it, you can hardly tell the computer is behind the screen when viewed head-on.

 

[msystems]

Very impressive, you've basically DIY'd a steam deck. What kind of platforms will it able to emulate do you think? Would it be able to run PS1 games?

 

[CC Ricers]

Very impressive, you've basically DIY'd a steam deck. What kind of platforms will it able to emulate do you think? Would it be able to run PS1 games?

Just more of a Steam Deck Light with a smaller 5.5" screen! Remember the YouTube video is someone else's build. I also want to push it further with a hardware upgrade in the future.

I already play several Steam games on it natively- including Portal 1 and 2 which run great. Some are slow to launch but most 2D games and many older 3D games are running on it. Using Gamescope you can reduce the resolution and have it mimic fullscreen mode for better performance than sticking with the full 1080p of this little screen.

I haven't yet tried a PS1 emulator, but PS1 games should be able to run very well here. I've already used PPSSPP and ReDream which run their respective PSP and Dreamcast games fine. It starts to hit a performance wall with GameCube emulation. The Dolphin emulator unfortunately performs worse on Linux than on Windows (using the Vulkan backend).

From here there are three options I could upgrade to:

LattePanda Alpha with m3-8100y - intel iGPU has 24CUs compared to the Delta's 12CU and about twice as expensive

Compute Stick with m3-6Y30 processor - same iGPU as the Alpha but much cheaper and less workable I/O (I would need a USB hub/splitter)

DFI GHF51 with Ryzen R1305G - costs as much as the Alpha, and I/O needs to be added, but has a Vega 3 iGPU, so it should be the best iGPU of all three.

The Compute Stick and DFI board would require expanding storage much like the Steam Deck, by using SD cards only.

 

[Elaman]

Garuda gang represent!

I never managed to put 2 and 2 together that Compute Stick was actually x86 architecture, that's a big deal.
Other than that, AMD RDNA2 seems to be the most significant upgrade for the last two years in terms of performance-per-watt, which is what portables "want", and so far RDNA2 seems to be exclusive to consoles...
There is also the Nvidia route: Jetson from Nvidia, but I suppose that is no-go?

 

[CC Ricers]

Garuda gang represent!

I never managed to put 2 and 2 together that Compute Stick was actually x86 architecture, that's a big deal.
Other than that, AMD RDNA2 seems to be the most significant upgrade for the last two years in terms of performance-per-watt, which is what portables "want", and so far RDNA2 seems to be exclusive to consoles...
There is also the Nvidia route: Jetson from Nvidia, but I suppose that is no-go?

I've only seen RDNA2 in the SteamDeck and some recent laptops. Probably won't see an SBC with it for a year or two so the Vega 3 would have to do. AMD Embedded R series is very power efficient.

The Nvidia Jetson is ARM, not x86 so I would only be able to run ARM operating systems, and native Steam gameplay would be unlikely. Would be sufficient if you wanted to stream gameplay or use emulators, though. But for my use case I want to play directly on Steam and other Linux/Wine games first, and emulators are second, so I will stick to x86 for this project.

 

[Valantar]

I've only seen RDNA2 in the SteamDeck and some recent laptops. Probably won't see an SBC with it for a year or two so the Vega 3 would have to do. AMD Embedded R series is very power efficient.

The Nvidia Jetson is ARM, not x86 so I would only be able to run ARM operating systems, and native Steam gameplay would be unlikely. Would be sufficient if you wanted to stream gameplay or use emulators, though. But for my use case I want to play directly on Steam and other Linux/Wine games first, and emulators are second, so I will stick to x86 for this project.

Yeah, I haven't seen AMD announce any embedded Ryzens based on the 6000-series die yet, so we'll likely have to wait for that. One potentially major issue with embedded chips on SBCs is also that they often don't get GPU driver updates at all, or at least so rarely as to make it a real problem. Heck, that's often the case for laptop iGPUs even. Hopefully AMD steps up their iGPU driver game now that they're pushing iGPU performance into really mainstream usable ranges.

 

[CC Ricers]

The LP Alpha is back in stock, and also more expensive than I expected. Like, $100 more than its previous price. I'm moving it to the bottom of my list for possible upgrades, which is too bad because it has a nice form factor and plenty of I/O.

That makes the Vega 3 option, even more attractive now. Requires more DIY work to get all the inputs and outputs I need working but the entire build can remain a very small package.

I'll probably pull the trigger on the Vega 3 board and I can sell one of my mini PCs for it.

 

[CC Ricers]

So, I eventually went for the cheapest option, the Core M3 stick. I installed a fresh copy of Garuda Linux with some updates. Started playing some 3D games on Steam and they run much better. Pretty happy to get a consistent 30 or higher FPS on many things especially Borderlands 2 one of my favorite all-time games.

The tiny form factor makes it easy to tuck behind the screen. Yet, because of its tiny size the fan has to work harder to cool it, and load temps go past 85 C, compared to 65 to 70 on the LatttePanda. I'll have to do some more tuning on the Intel CPU to get the best power balance between the CPU and iGPU and keep temps down.

 

[CC Ricers]

For some reason my Steam Proton games stopped working. They wouldn't launch, either hang with the launching message, or say there's something wrong with the compatibility tool. Native Linux games still work fine. I deleted all the contents of my Steam folder and re-installed everything, tried some games but still having this issue.

It's strange as I didn't have this problem with the last time I installed Garuda on the other computer. I will give it another go and re-install the whole OS as there wasn't much that I've done anyway.

 

[CC Ricers]

Yeah, looks like I'm going back to using the LattePanda It may have a weaker GPU but having the extra I/O built in is too convenient, plus there's still the option to upgrade to a better LP if I so choose.

I'm taking a modular approach to designing the enclosure this time. It will be split into different parts that can be connected together. The base component includes the LP board itself and a 5" 720p screen. The screen is IPS and powered only with HDMI. It's pretty convenient although it does get fussy to use at times. Doesn't always display a picture when changing display modes so forcing a reset, or sleep and wakeup to get the picture back on.

The base component's design is inspired by the Seeed ReTerminal.

It requires an external power source, and so will mine. It should be made to connect to battery modules for a portable power source that can be recharged. So here's my take on it.

Part of the case includes a XT-30 connector for the power. It may be overkill because I won't need very high current loads, but it sure looks nice and clean. The large open area is for connecting the HDMI ribbon cable. The cable will be tightly wound unto itself inside the case, and this opening is just to make it easier to position as I assemble the whole thing. Still missing are the heatsink fan vent holes. I should not forget to add those!

Some renders of it in a transparent polycarbonate case, just to show the parts inside.

The USB ports are all accessible on the opposite side and like the ReTerminal also has a IDC connector for some of the GPIO. It's not easy to get the scale of how small this thing is, but looking at the connectors should help.

 

[msystems]

You might not have room for the extra width, but here is the mountable version of the plug for enclosures

Edit: whoops that is xt60. You're going even smaller with xt30. That's small!!

It's not easy to get the scale of how small this thing is

+

 

[CC Ricers]

Yes, the XT30 is what I'm using as XT60 won't fit easily. Gotta work around it somehow. But that's part of the challenge of going ultra SFF!

I am trying out a different screen that I bought used on eBay. It didn't have a specific model name but I was able to identify it as this 5 inch IPS display as sold by Seeed Studio. They don't sell them anymore and it's surprisingly hard to find a 720p panel of this exact size so I guess I lucked out.

It lacks a touch screen and its image quality doesn't match the OLED screen (though still good being IPS), but it does have a few advantages. First, I think it hits the sweet spot of pixel density for this size. 480p looks too coarse and not suited for most desktop UIs. 1080p gives me more detail than I need, plus I do see some interface elements stuttering a bit because of the slower GPU.

Steam Big Picture Mode's interface in particular lags a bit in 1080p resolution compared to 720p. Gamescope also tends to run slower with upscaling to 1080p because of this bottleneck. These factors alone push this 720p in my favor for using it over the 1080p despite its other shortcomings. I'd rather have smoother framerates in favor of the finer quality with more pixels.

It does have a big annoyance though- this screen is super finicky with display modes. Upon first boot, it does not display an image but the backlight still turns on. The power button on its side turns on and off the backlight but only by unplugging the HDMI plug and re-inserting it do I get the image to show up. After that it all works as intended. This isn't something I want to keep doing every time I turn on the computer. So, guess I gotta do some hacky workaround somehow. Do I create a custom HDMI cable painstakingly soldering many wires with an on/off switch on one of them? It does pose a unique problem that a HDMI switching box is too much and not exactly what I'm trying to do.

Instead of attempting to make a custom super-short cable, I tried instead to short the 5V and ground pins to temporarily disable it so as to "unplug" without physically removing the whole thing. Following this pinout diagram I gave that a quick try shorting the pins with a small screwdriver. So after boot, I got no image as usual and after poking both pins 17 and 18 the display turned off momentarily and then turned back on showing the session screen.

It's still rather hacky, needing to do this every time I need to boot, but still better than unplugging every time and risk damaging the connector. My planned way to make this more manageable is to solder wires to pins 17 and 18 and connect with a momentary push button. I can then just push this button to briefly short the pins and the button can be placed somewhere in the housing. A toggle switch might also be added to take care of the backlight. Sometimes the light stays on after shutting down the PC.

Knowing this I can continue designing the enclosure but still not sure how the screen would hold up with such a "feature" added to the video plug. Or whether doing this too much would cause damage to the backlight.

 

[CC Ricers]

Well guess what, Steam Proton stopped working on my main LattePanda build too. And does so silently without any errors. Quite annoying and nothing shows up in error logs. From other peoples' reports on this issue, it mainly rests on conflicting filesystems, especially NTFS. But otherwise I don't see any probable cause. Though with Garuda they don't use the more obvious choice of ext4 and require using Btrfs. I've only had this install for a week and a half and the partial upgrades I did with both my builds may have broken Proton and Wine compatibility. Removing the entire Steam folder and re-installing Steam hasn't fixed it either.

At this point I'm going to replace Garuda with Manjaro KDE on both builds as I have far more time using that for my daily driver and trust it well. Steam Proton and Lutris hardly gave me problems when I was using Manjaro.

 

[Elaman]

Well guess what, Steam Proton stopped working on my main LattePanda build too. And does so silently without any errors. Quite annoying and nothing shows up in error logs. From other peoples' reports on this issue, it mainly rests on conflicting filesystems, especially NTFS. But otherwise I don't see any probable cause. Though with Garuda they don't use the more obvious choice of ext4 and require using Btrfs. I've only had this install for a week and a half and the partial upgrades I did with both my builds may have broken Proton and Wine compatibility. Removing the entire Steam folder and re-installing Steam hasn't fixed it either.

At this point I'm going to replace Garuda with Manjaro KDE on both builds as I have far more time using that for my daily driver and trust it well. Steam Proton and Lutris hardly gave me problems when I was using Manjaro.

Unfortunately I didn't put two and two together until you mentioned it, but in my tests I have gotten a minimum of +5º on the average drive temperature (SSD) only by using BTRFS over EXT4. Sometimes more than 5º. Probably not a good filesystem for a handheld.

 

[CC Ricers]

@Elaman gonna have to check that out since I might hop back to Garuda again. Not sure if the 5 degree increase will matter much. But either way the SSD area might be sandwiched between the back of the screen and the rest of the board so we'll see how that goes.

In the meantime I turned the LattePanda into a Steam Deck! Well, sorta. It's the current build of the Steam Deck interface available with a few changes to the Steam folder contents. Now I can get a better idea of what a "lite" version of a Steam Deck could be.

The UI is a bit laggy unlike Big Picture at the same resolution, but I think that's reasonable given that for now, it seems to be built for a limited hardware spec of processors. Still, it's very responsive and not bad for a mobile Celeron SBC.

The more I use it the more I realize how useful the touch panel is for the interface. This particular screen does not have a touch panel and it is a bit smaller than the 5.5" AMOLED. I'm still testing things around with the touch-free one. Then I'll see how the AMOLED performs given it's a 1080p screen.

 

[CC Ricers]

I'm going to forego the LP Delta board and go with a Celeron mini PC that's a bit more powerful. That takes me back to.. the Larkbox. Yes, it's back to where I started But I decided I would take more raw performance in a tiny PC over ease of convenience with extra I/O.

The Larkbox's Celeron J4105 > N4120, has 2GB more RAM and runs it in dual channel. And we know how much that dual channel matters with iGPU performance.

Gamescope is also a godsend for low-spec PCs like these. I can run games at very low resolutions where they would otherwise struggle in HD resolutions with the Intel iGPU. But there's still a performance hit here with upscaling low-resolution images as it tends to drop more frames when upscaling to 1080p vs. 720p. So the 720p non-touch screen has the advantage here.

Therefore, still using the smaller 5" screen and the mini case design that can fit in your pocket. Designing the battery enclosure should be interesting. It would basically be a power bank with dimensions that fit in with the PC case.

 

[Valantar]

I'm going to forego the LP Delta board and go with a Celeron mini PC that's a bit more powerful. That takes me back to.. the Larkbox. Yes, it's back to where I started But I decided I would take more raw performance in a tiny PC over ease of convenience with extra I/O.

The Larkbox's Celeron J4105 > N4120, has 2GB more RAM and runs it in dual channel. And we know how much that dual channel matters with iGPU performance.

Gamescope is also a godsend for low-spec PCs like these. I can run games at very low resolutions where they would otherwise struggle in HD resolutions with the Intel iGPU. But there's still a performance hit here with upscaling low-resolution images as it tends to drop more frames when upscaling to 1080p vs. 720p. So the 720p non-touch screen has the advantage here.

Therefore, still using the smaller 5" screen and the mini case design that can fit in your pocket. Designing the battery enclosure should be interesting. It would basically be a power bank with dimensions that fit in with the PC case.

Sounds like a good set of prioritizations. And as an old Norwegian mountaineering saying goes, there's no shame in turning back. Looking forward to seeing it come together!

Btw, not that this is remotely in the same budget category, but have you seen that Framework have started selling their laptop motherboards standalone? They're not tiny, but quite small, and might be used for a higher end DIY handheld. At $399 for the i5-1135G7 version they're not that bad. Plus of course you can get an original battery that hooks directly to the motherboard, though that's not quite handheld-friendly in size.

 

[CC Ricers]

Sounds like a good set of prioritizations. And as an old Norwegian mountaineering saying goes, there's no shame in turning back. Looking forward to seeing it come together!

Btw, not that this is remotely in the same budget category, but have you seen that Framework have started selling their laptop motherboards standalone? They're not tiny, but quite small, and might be used for a higher end DIY handheld. At $399 for the i5-1135G7 version they're not that bad. Plus of course you can get an original battery that hooks directly to the motherboard, though that's not quite handheld-friendly in size.

Oh they're on sale now? That's good to know. I'll keep an eye on those if I want to make a more powerful slim portable PC. There's also a blog entry where one of the staff made a 3D printed enclosure for it. It gives me a better sense of the scale (the plug in modules are much smaller than they first appear).

 

[CC Ricers]

The Framework PC is looking more tempting each day, and some DIY projects are slowly coming out that are using their mainboards.

I've got mini PCs galore (not really, but I have a few) and plan on selling some in order to get the mainboard for a custom portable case build. Two NUCs and maybe stick PCs I don't need. Maybe I'll buy the battery too as it's got a pretty good capacity.

 

[CC Ricers]

Framework is clearing out their supply of 11th gen Intel motherboards to make way for 12th gen, so I grabbed a 1135G7 board at the sale price. It should be coming in a week or two. I downloaded the CAD file for their 3D printable case and began modifying it, to use as a base for my portable model.


It's still not yet very different from the original, but I've made it 2cm shorter, to 28cm which is about the same size as the OneXPlayer. Going by similar specs, I could fit a screen between 8 and 9 inches in size. AliExpress carries several of this size with a 1280x800 or 2560x1600 resolution (same as the OneXPlayer). I still need a way to power it as I didn't purchase a battery. There are a couple GaN power chargers that I can use, though.