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If the engine in your car stutters once in a while… is it defective? If your LCD monitor has a dead pixel, is it defective? That is a question of quality. Ro

If the engine in your car stutters once in a while… is it defective? If your LCD monitor has a dead pixel, is it defective? That is a question of quality. Rowhammer showed that what previously was acceptable quality is no longer so.

mort96 4y ago
> If your LCD monitor has a dead pixel, is it defective? Yes.
- yunohn 4y ago
  Dead pixels happen, it doesn’t mean the whole panel is defective.
  - 1letterunixname 4y ago
    It's the stipulative definition of "defective" as a term. One could assess it with functional and nonfunctional criteria. Consumer A demands perfection for full brightness video in darkness while customer B requires serviceability only to see a large letter X or O.
- DougMerritt 4y ago
  So you always buy Class I monitors, guaranteed zero dead pixels, not the affordable Class II monitors with up to 15 dead pixels? [1] [1] https://en.wikipedia.org/wiki/ISO_13406-2#Pixel_Fault_Classes https://en.wikipedia.org/wiki/ISO_13406-2#Pixel_Fault_Classe...
  - mort96 4y ago
    I must admit, I don't pay attention to that. But my monitors don't have dead pixels, and if they had dead pixels, I would absolutely consider that a defective monitor. The class presumably just determines whether I can get the manufacturer to fix it for free or not.
    - DougMerritt 4y ago
      Yes, but they're also choosing the monitors that pass QA best. It may be that all of their monitors have zero defects, but that is statistically unlikely. Look at chip manufacturing. They really care about high yields, but there are always defects, 20 years ago and today as well. It's an issue with manufacturing in general. Perfection is typically impossible to achieve. Maybe not always, but typically. Back to the main issue, since modern monitors are quite high resolution, you and I might both have a few dead pixels, or more likely a few that have pixels that are half-dead (dim) in one channel (of red/blue/green), and we just don't notice on our desktops -- and it would usually take careful examination to spot them even on a pure white screen. Your mileage may vary, of course.
      - mort96 4y ago
        Dead pixels which are just dimmer than usual is okay, some variance is expected. But if a monitor has that kind of dead pixel that's stuck displaying a bright white or green or something even when the rest of the screen is black, the screen is 100% defective, whatever the manufacturer's QA standards might say.
    - sroussey 4y ago
      As an EE, I’m shocked computers work at all, and so reliably. If you knew how the sausage was made you would be horrified.
- pfortuny 4y ago
  From Dell: A display with 1 to 5 fixed subpixel is considered normal and within industry standards https://www.dell.com/support/kbdoc/es-es/000126004/dell-display-pixel-guidelines?lang=en https://www.dell.com/support/kbdoc/es-es/000126004/dell-disp...
  - mort96 4y ago
    Yeah, so Dell sells defective monitors and doesn't serve them under warranty. Doesn't mean they're not defective.
myself248 4y ago
If the engine in my car runs fine on whatever gas for 10 years, but when I put the same gas in the tank 50 tank-fuls in a row and suddenly the engine turns into a pink flamingo, yes it is defective. If my LCD monitor displays any image I want, but when I try to show an image of a checkerboard it loses sync with the incoming signal, yes it is defective. (There were a number of similar problems in the telephone network around the introduction of T1 signaling, and it's why the 1000Hz milliwatt test tone was changed to 1004Hz.) These things were never acceptable.
- orbz 4y ago
  The difference in this case is there’s a malicious party acting against the system too. It would be like one gas station you go to throwing some sugar in the tank just to mess with you.

mort96 4y ago

> If your LCD monitor has a dead pixel, is it defective? Yes.

yunohn 4y ago
Dead pixels happen, it doesn’t mean the whole panel is defective.
- 1letterunixname 4y ago
  It's the stipulative definition of "defective" as a term. One could assess it with functional and nonfunctional criteria. Consumer A demands perfection for full brightness video in darkness while customer B requires serviceability only to see a large letter X or O.
DougMerritt 4y ago
So you always buy Class I monitors, guaranteed zero dead pixels, not the affordable Class II monitors with up to 15 dead pixels? [1] [1] https://en.wikipedia.org/wiki/ISO_13406-2#Pixel_Fault_Classes https://en.wikipedia.org/wiki/ISO_13406-2#Pixel_Fault_Classe...
- mort96 4y ago
  I must admit, I don't pay attention to that. But my monitors don't have dead pixels, and if they had dead pixels, I would absolutely consider that a defective monitor. The class presumably just determines whether I can get the manufacturer to fix it for free or not.
  - DougMerritt 4y ago
    Yes, but they're also choosing the monitors that pass QA best. It may be that all of their monitors have zero defects, but that is statistically unlikely. Look at chip manufacturing. They really care about high yields, but there are always defects, 20 years ago and today as well. It's an issue with manufacturing in general. Perfection is typically impossible to achieve. Maybe not always, but typically. Back to the main issue, since modern monitors are quite high resolution, you and I might both have a few dead pixels, or more likely a few that have pixels that are half-dead (dim) in one channel (of red/blue/green), and we just don't notice on our desktops -- and it would usually take careful examination to spot them even on a pure white screen. Your mileage may vary, of course.
    - mort96 4y ago
      Dead pixels which are just dimmer than usual is okay, some variance is expected. But if a monitor has that kind of dead pixel that's stuck displaying a bright white or green or something even when the rest of the screen is black, the screen is 100% defective, whatever the manufacturer's QA standards might say.
  - sroussey 4y ago
    As an EE, I’m shocked computers work at all, and so reliably. If you knew how the sausage was made you would be horrified.
pfortuny 4y ago
From Dell: A display with 1 to 5 fixed subpixel is considered normal and within industry standards https://www.dell.com/support/kbdoc/es-es/000126004/dell-display-pixel-guidelines?lang=en https://www.dell.com/support/kbdoc/es-es/000126004/dell-disp...
- mort96 4y ago
  Yeah, so Dell sells defective monitors and doesn't serve them under warranty. Doesn't mean they're not defective.

myself248 4y ago

If the engine in my car runs fine on whatever gas for 10 years, but when I put the same gas in the tank 50 tank-fuls in a row and suddenly the engine turns into a pink flamingo, yes it is defective. If my LCD monitor displays any image I want, but when I try to show an image of a checkerboard it loses sync with the incoming signal, yes it is defective. (There were a number of similar problems in the telephone network around the introduction of T1 signaling, and it's why the 1000Hz milliwatt test tone was changed to 1004Hz.) These things were never acceptable.

orbz 4y ago
The difference in this case is there’s a malicious party acting against the system too. It would be like one gas station you go to throwing some sugar in the tank just to mess with you.