Poking At The Radxa Dragon Q8B Raspberry Pi 5 Killer

Although the asking price of $209 plus shipping seems high for the Radxa Dragon Q8B, featuring the Qualcomm SC8280XP and 8 GB of LPDDR4X, this is 2026, and amid the RAMpocalypse, even the 8 GB LPDDR4X-equipped Raspberry Pi 5 now costs $175. This, to [Jeff Geerling], makes it fair to directly compare the two to see whether you may want to consider this board for more intense computing purposes.

There’s also a written summary of the results and details in a GitHub issue, though the direct comparison with the Raspberry Pi 5 is in the video.

Although this Qualcomm SoC isn’t new, its primary use is for Windows laptops, which gives somewhat of a hint as to what its performance may be like, tempered by the fact that it was announced in 2021.

The Dragon QXB offers about 2x everything over the RPi5, plus Windows and UEFI support. For Linux, it appears that you still need customized images, which seems perplexing in light of the UEFI aspect. You also have to pick between different Linux images from Radxa and use their Rsetup update tool, making it a less than newbie-friendly offering.

Continue reading “Poking At The Radxa Dragon Q8B Raspberry Pi 5 Killer” →

Embedded 3D Printing With Liquids On A Bricked Prusa FDM Printer

Recently [Riley] got his paws on an old Prusa i3 FDM printer that had clearly seen better days, with a hot-end that had suffered an explosive blow-out. For the project he had in mind this was of course perfect, as his intention was to replace the hot-end with a syringe system for embedded 3D printing (E3DP), which uses a supportive medium to allow for the printing of materials and structures that would be impossible with just air.

Generally in additive manufacturing (AM) methods like fused deposition modelling (FDM) the material is extruded onto a build plate or a previous layer where it solidifies. This works great for materials like thermoplastics, but for other materials having only the surrounding air as support is just a recipe for a big mess. With E3DP the liquid is instead extruded into a supportive material at a selectable depth and volume, opening up a whole range of possibilities.

Continue reading “Embedded 3D Printing With Liquids On A Bricked Prusa FDM Printer” →

Introducing The Garlic-Powered Door And Window Sensor

Most home security sensors require a chemical battery or external power source to operate, which can be a point of weakness. If the battery in a window or door sensor dies overnight and nobody is there to swap it, it might miss that one intruder or mess up your carefully curated home automation system. In that sense self-powered sensors are rather interesting, such as this one by [Manas Tiwari] and [Deepak Bharti] that is based around the triboelectric effect.

The research article is sadly paywalled, but the IEEE Spectrum article covers all the salient details. The sensor uses ground up garlic peel for the positive side of this triboelectric nanogenerator (TENG) as they call it, with a sheet of polyethylene (PE) forming the negative side. Once installed on a door frame, opening said door generates about 210 VAC with a 45 µA short circuit current. A dual-side layer of garlic peel bumps this up to 400 VAC and 65 µA.

As installed, the researchers used this generated current to detect changes using a separate MCU running off a powerbank, which obviously does not really solve the ‘running out of charge’ issue. The generated power could conceivably be used to send a brief wireless packet to a receiver elsewhere in the room, somewhat like the Bluetooth link in the example, but more low-power.

The researchers also reported that this sensor was still functional after half a year in storage, and survived 200 stress cycles, which seems like a good start for what appears to be a very cheap sensor to construct.

Turning A Run-Over Samsung Galaxy S23 Into A Gaming PC

Repurposing old smartphones for more general purpose computing isn’t a new thing, but the project by [LastComputer] ups the ante by going from a Samsung Galaxy S23 that looks like it got run over by at least a few cars to a very serviceable gaming computer, courtesy of its Snapdragon 8 Gen 2 SoC.

The somehow still working but definitely worse for wear phone was purchased for 1,700 Ukrainian Hryvnia (~$40). It being SIM locked also helped reduce the price, even if someone had somehow wanted to use it again as a phone. Since the SoC inside is also used in quite capable gaming handhelds, but with good cooling, that would be a real waste.

Converting it into proper gaming system requires some careful disassembly, some gentle whacking with a hammer to straighten out the frame and a new battery as the mainboard won’t work without one installed.

A 3D-printed phone case glued to an SSD cage for the 512 GB SSD serves as the enclosure, along with two USB hubs, one of which also provides HDMI output. For the active cooling system a heatsink was hot-glued to the vapor chamber with a properly sized fan mounted to it. Here we could definitely see some zip ties being added to prevent it from falling off.

Compared to running the phone in its stock cooling configuration this shaves off about seven degrees C, with thermal throttling noticeably reduced. This consequently provides a much better desktop experience in Samsung’s DeX (Desktop eXperience) desktop mode, which is what’s used for running applications and games.

Running God of War as an emulated PS2 game works pretty well, as does running games with the Dolphin emulator and the GameHub app using which PC games on Steam, GoG and others can be run. Although you can also install other OSes on the phone hardware, Samsung DeX doesn’t appear to be a bad option if you happen to repurpose a high-end Samsung phone that supports this mode.

Continue reading “Turning A Run-Over Samsung Galaxy S23 Into A Gaming PC” →

Repairing A Couple Of Very Expensive Registered DDR5 RAM Sticks

It’s definitely a sign of the times when repair shops get handed sticks of registered ECC DDR5 RAM by businesses to try and fix, rather than just tossing the defective ones and slotting in a fresh bunch. This is how [northwestrepair] ended up with two of these ECC RDIMMs, with a current market valuation of a rather nice budget car.

The 128 GB stick was first on the bench, with the fault being that it would fail DDR5 training on boot. This suggests that one or more of the DRAM BGA packages had developed a cracked solder joint, which is something that you could conceivably fix with more diagnosing and testing for a single IC reballing.

In this case doing a reflow cycle was enough to bring the RAM back to life, with the DDR5 training now passing without issues in a test system.

For the 256 GB stick things wouldn’t be so easy, as it seemed completely dead. This suggested a dead PMIC, as this is the component on DDR5 RAM responsible for ensuring that the DRAM ICs even power on. The SPD ROM was another option, so that got swapped first, which does require reprogramming the RDIMM. For this the earlier SPD dump image was reflashed, but swapping this chip made no difference.

After some additional reflowing of a few suspect ICs, still nothing happened. Following this a lot of reballing and other troubleshooting steps followed, only for the problem to be one shorted MLCC and a broken PMIC, potentially caused by whoever dropped said RDIMM onto the server room floor.

Cracked MLCCs do appear to be a very common cause of failures, as they’re often used as filter capacitors, same as for this RDIMM. Checking for shorts across a number of such MLCCs can be a good way to shorten a diagnostic cycle. Since this RDIMM was dropped, reballing every IC probably was still a good move as this may have cracked some solder balls.

Continue reading “Repairing A Couple Of Very Expensive Registered DDR5 RAM Sticks” →

Scientists Create Hexagonal Packed Ice At Extreme Pressures

One of the problems with planetary science is that you generally cannot easily investigate the exact conditions in their interior, so you’re left to extrapolate what is happening inside them based on surface scans. One of the resulting questions is what ice giants like Neptune and Uranus in Earth’s solar system have exactly at their core. We do know that it is mostly rocks and ice, but what kind of ice you end up with at these intense pressures is a good question that [Alexis Forestier] et al. set out to answer, with their results published in a Physical Review Letter paper (ArXiv preprint).

It’s noteworthy that there isn’t just water ice at these planetary cores, with this study only investigating water ice specifically. In order to get the water to the pressures it would experience courtesy of ice giant gravity, a diamond anvil was used, with synchrotron x-ray diffraction allowing for the changes to the sample to be observed.

The phase diagram of water includes a number of phases beyond what us Earth-dwellers would call ‘ice’, with at higher pressures above about 80 GPa the formation of ice X, featuring a body-centered cubic (BCC) oxygen sublattice. Subsequent discovered phases were face-centered cubic (FCC) and now hexagonal close-packed (HCP) ice, all differing in the packing of the oxygen sublattice.

In addition to extreme pressures, temperatures also had to be increased by using the laser heating feature of the diamond anvil. At around 2,000K and over 200 GPa the HCP phase was found, with a mixed FCC-HCP phase at intermediate pressures.

Although not immediately providing answers to questions pertaining to the aforementioned ice giants, it gives planetary scientists yet another clue that they can use in future investigations, as well as provide more insight into this most fascinating phase of water that’s actually its own little galaxy of phases.

The EDG C++ Compiler Frontend Has Been Open Sourced

Recently [John Spicer] of the EDG C++ compiler front-end project announced that the project will be made open source, from now on managed by the non-profit C++ Alliance. Related source code can be found on the GitHub account.

The Edison Design Group (EDG) is a US company which has made compiler front-ends since 1988, previously also for Java and Fortran. They are used in the Intel C++ compiler, Microsoft’s VC++, NVIDIA’s CUDA compiler, as well as many other commercial products. Last year the decision was made to shutdown the company in 2026 and transition to an open source model, with the details outlined on the EDGCPP site.

Although far from the only C++ front-end, EDGCPP will be very interesting still for supporting bleeding-edge features and having been used in such wide-ranging, demanding applications by a host of commercial customers. For most of us C++ developers our contact with it will have been via the MSVC and Intel Compiler Collection tooling, but of course it’s just one part of the entire toolset.

We’re looking forward to seeing what this means for the wider open source C++ ecosystem, especially as it pertains to GCC and LLVM’s Clang.