It is said that you’re not a sysadmin if you haven’t warmed up a sandwich on server. OK, it’s not widely said; we made it up, and only said it once, coincidentally enough after heating up a sandwich on a server. But we stand by the central thesis: never let a good source of excess thermal energy go to waste.
[Joseph Marlin] is in the same camp, but it’s not lunch that he’s warming up. Instead, he’s using the heat generated by his Folding@Home rig to sprout seeds for beautiful tropical flowers. A native of South Africa Strelitzia reginae, better known as the striking blue and orange Bird of Paradise flower, prefers a temperature of at least 80° F (27° C) for the two months its seeds take to sprout. With all the extra CPU cycles on a spare laptop churning out warm air, [Joseph] rigged an incubator of sorts from a cardboard box. A 3D-printed scoop snaps over the fan output on the laptop and funnels warm air into the grow chamber. This keeps the interior temperature about 15 degrees above ambient, which should be good enough for the seeds to sprout. He says that elaborations for future versions could include an Arduino and a servo-controlled shutter to regulate the temperature, which seems like a good idea.
The Bird of Paradise is a spectacular flower, but if growing beautiful things isn’t your style, such a rig could easily sprout tomatoes or peppers or get onions off to a good start. No matter what you grow, you’ll need to basics of spinning up a Folding@Home rig, which is something we can help with, of course.
Join us on Wednesday, March 25 at noon Pacific for the Side-Channel Attacks Hack Chat with Samy Kamkar!
In the world of computer security, the good news is that a lot of vendors are finally taking security seriously now, with the result that direct attacks are harder to pull off. The bad news is that in a lot of cases, they’re still leaving the side-door wide open. Side-channel attacks come in all sorts of flavors, but they all have something in common: they leak information about the state of a system through an unexpected vector. From monitoring the sounds that the keyboard makes as you type to watching the minute vibrations of a potato chip bag in response to a nearby conversation, side-channel attacks take advantage of these leaks to exfiltrate information.
Side-channel exploits can be the bread and butter of black hat hackers, but understanding them can be useful to those of us who are more interested in protecting systems, or perhaps to inform our reverse engineering efforts. Samy Kamkar knows quite a bit more than a thing or two about side-channel attacks, so much so that he gave a great talk at the 2019 Hackaday Superconference on just that topic. He’ll be dropping by the Hack Chat to “extend and enhance” that talk, and to answer your questions about side-channel exploits, and discuss the reverse engineering potential they offer. Join us and learn more about this fascinating world, where the complexity of systems leads to unintended consequences that could come back to bite you, or perhaps even help you.
Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, March 25 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.
Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Continue reading “Side-Channel Attacks Hack Chat With Samy Kamkar”
When the first thermal cyclers for the polymerase chain reaction came out in the 1980s, they were as expensive as a market driven by grant money could make them. Things haven’t got much better over the years, largely shutting STEM classes and biohackers out of the PCR market. That may be about to change, though, if the €99.00 PocketPCR thermal cycler takes hold.
PCR amplifies DNA in a three-step process: denaturation, which melts double-stranded DNA into single strands; annealing, which lets small pieces of primer DNA bind to either side of the region of interest; and elongation, where the enzyme DNA polymerase zips along the single strands starting at the primer to replicate the DNA. The cycle repeats and copies of the original DNA accumulate exponentially. Like any thermal cycler, [Urs Gaudenz]’s PocketPCR automates those temperature shifts, using a combination of PCB-mounted heating elements and a cooling fan. The coils rapidly heat a reaction block up to the 99°C denaturation temperature, the fan brings that down to the 68°C needed for annealing, and then the temperature ramps back up to 72°C for elongation with thermostable DNA polymerase. PID loops keep the reaction temperature precisely controlled. The whole thing is, as the name suggests, small enough to fit in a pocket, and can either be purchased in kit form or scratch-built from the build files on GitHub.
We applaud [Urs]’ efforts to get the power of PCR into the hands of citizen scientists. Quick and dirty thermal cyclers are one thing, but Pocket PCR has a great fit and finish that makes it more accessible.
Thanks to [Abe Tusk] for the tip.
Problem: your electronic load works fine, except for the occasional MOSFET bursting into flames. Solution: do what [tbladykas] did, and build a water-cooled electronic load.
One can quibble that perhaps there are other ways to go about preventing your MOSFETs from burning, including changes to the electrical design. But he decided to take a page from [Kerry Wong]’s design book and go big. [Kerry]’s electronic load was air-cooled and capable of sinking 100 amps; [tbladykas] only needed 60 or 70 amps or so. Since he had an all-in-one liquid CPU cooler on hand, it was only natural to use that for cooling.
The IXYS linear MOSFET dangles off the end of the controller PCB, where the TO-247 device is soldered directly to the copper cold plate of the AiO cooler. This might seem sketchy as the solder could melt if things got out of hand, but then again drilling and tapping the cold plate could lead to leakage of the thermal coupling fluid. It hasn’t had any rigorous testing yet – his guesstimate is 300 Watts dissipation at this point – but as his primary endpoint was to stop the MOSFET fires, the exact details aren’t that important.
We’ve seen a fair number of liquid-cooled Raspberry Pis and Arduinos before, but we can’t find an example of a liquid-cooled electronic load. Perhaps [tbladykas] is onto something with this design.
Under the right circumstances, Gaussian blurring can make an image seem more clearly defined. [DZL] demonstrates exactly this with a lightweight and compact Gaussian interpolation routine to make the low-resolution thermal sensor data display much better on a small OLED.
[DZL] used an MLX90640 sensor to create a DIY thermal imager with a small OLED display, but since the sensor is relatively low-resolution at 32×24, displaying the data directly looks awfully blocky. Gaussian interpolation to improve the display looks really good, but it turns out that the full Gaussian interpolation isn’t a trivial calculation write on your own. Since [DZL] wanted to implement it on a microcontroller, the lightweight implementation was born. The project page walks through the details of Gaussian interpolation and how some effective shortcuts were made, so be sure to give it a look.
The MLX90640 sensor also makes an appearance in the Open Thermal Camera, one of the entries for the 2019 Hackaday Prize. If you’re interested in thermal imaging, don’t miss this teardown of a thermal imaging camera.
Although Iceland is now a popular destination for the day-tripping selfie-seeking Instagrammer who rents a 4×4, drives it off road onto delicate ecosystems and then videos the ensuing rescue when the cops arrive, there are still some genuine photographers prepared to put a huge amount of time and effort into their art. [Dheera Venkatraman] is one of the latter and produces composite photos using a relatively low resolution thermal camera and DIY pan and tilt rig.
Whilst we don’t have the exact details, we think that, since the Seek Reveal Pro camera used has a resolution of 320 x 240, [Dheera] would have had to take at least 20 photos for each panoramic shot. In post processing, the shots were meticulously recombined into stunning landscape photos which are a real inspiration to anybody interested in photography.
If you do go to Iceland you might find the traditional food a little challenging to those not raised upon it, nor would you go there for a stag night as beer is eyewateringly expensive. But if you enjoy uninhabitable, desolate, dramatic landscapes there is a huge range of possibilities for the photographer from rugged, frozen lava flows to extra terrestrial ‘Martian’ crater-scapes, if you know where to find them.
[Dheera’s] blog contains some more information about his Iceland photography and there’s a Github repsoitory too. And if you cant afford a $699 Seek Reveal Pro, maybe try building one yourself.
Every year, we demand our computers to be ever faster, capable of delivering progressively more eye-watering graphics and doing it all as reliably as ever. Unfortunately, sometimes, new designs miss the mark. [Cloakedbug] was having issues with voltage regulator temperatures on an ASUS Strix VEGA 64 — one of the latest RADEON graphics cards on the market — and decided to investigate.
Right away, issues were apparent; one of the main thermal pads was making poor contact with the FETs it was intended to carry heat for, and was poorly sized to boot. In a show of poor quality, the pad wasn’t nicely sized for the aluminium plate it was attached to, and was applied in a rather haphazard manner. Suspecting this was perhaps one of the root causes of the card running hot, the decision was made to replace the pad with something more suitable.
Specifying a thicker pad that was properly sized to the heatsink plate was the order of the day, and a couple of other smaller heatsink pads were also replaced, all with Thermal Grizzly Minus Pad 8. [Cloakedbug] reports a temperature drop of over 30 degrees C under load on the VR SOC bank, down from 115 C initially. It sounds like this will go a long way to keeping the card happy and healthy over time. Looking around the web, there’s definitely a few reports of thermal issues out there, so this could be a useful fix if you’re having trouble with the same card at home.
In the end, it’s a simple, tidy fix to an expensive piece of hardware that really should have shipped with this sorted from the factory. We’ve seen a fair few thermal fixes over the years here, like this one involving a thermal camera as a diagnosis tool.
[Thanks to Keith O for the tip!]