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Comment Quanta (Score 1) 129

I'm guessing the spoofed company is Quanta. There's a lot of surplus last-gen equipment on eBay (meaning companies would be upgrading), and I believe Facebook used them as an OEM for their Open Compute nodes (Quanta Mindmill). Not sure who else uses Quanta OEM in particular, but some of their switches appear to be reference designs for Dell, etc.

Comment Electromagnetic Immunity (Score 5, Interesting) 173

I get to deal with weird stuff like this at work all the time. Based on the behavior, I'd guess there's a clock and/or data running at a harmonic of the wifi data. Freezing seems to indicate it's coupling into the core of the LCD controller board, which again I would guess is a timing violation or data corruption. Where it's coupling in is a bit hard to determine without further testing. It could be the video cable, could be the power cable (not likely), could be the LCD panel itself acting as an antenna, or an interconnect cable that is poorly shielded or just the right length to couple in wifi. It could also be power supply ripple caused by a feedback loop getting energy coupled in, though if that's possible then there's not enough timing margin to begin with.

I suggest a number of tests to narrow down details of the source:
- Test 2.4GHz and 5GHz independently. Test each wifi channel independently.
- Try a different length cable. Try a different brand cable. Does this monitor remain on with nothing connected? If so then try it with no cable, or no PC at the end.
- Try different antenna angles. Try different TX power levels (at what level does it start).
https://tech.slashdot.org/stor...
Based on those results I'd have more recommendations.

If someone wants the real root cause, feel free to send me one and I'll debug it (though it will probably require disassembly).

Comment Race Conditions (Score 1) 230

Reminds me of debugging errors related to digital logic race conditions. When you are on the edge of meeting timing, a slight shift in the wrong direction can cause the result to be incorrect, sometimes with an order of randomness. Until you violate that timing you have the feeling of security since everything is going smoothly. I'm sure there's a more mathematical way to explain this, but similarly I think much more testing could be done to understand what variables effect the outcome. It would be interesting to see more details, such as how many pixels must be modified for a failure? To what magnitude do the pixels have to be changed by? Is there a tradeoff between # of pixels and magnitude of change per pixel? Are certain pixels more important than others (edge detection for example)?

Submission + - Apple A4 Processor Teardown (eetimes.com)

Plocmstart writes: Here's what EETimes.com is claiming to be the first teardown of the A4 processor. "Apple's iPad chip is a single-core ARM A8 made by Samsung. Through various benchmarking testing, UBM TechInsights was able to find out the details of the A4 processor."

Comment What about shutdown? (Score 3, Informative) 326

Given the flowcharts (not the shiny video that catches your attention first) it appears that instead of shutting down, they simply reboot the system and once it reaches the state where the OS has finished loaded it then goes to sleep or hibernate. Once you power it back on it just returns to the freshly loaded OS.
So it appears that while it starts up faster, you should end up spending more time shutting down (actually rebooting and reloading the OS). You could also do this manually by rebooting Windows and once it gets to the desktop/login screen go into hibernate/sleep.

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"The eleventh commandment was `Thou Shalt Compute' or `Thou Shalt Not Compute' -- I forget which." -- Epigrams in Programming, ACM SIGPLAN Sept. 1982

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