35

I've been seeing this since the late 1990s: https://www.youtube.com/watch?v=eKy9fV_zX_o

Was this a hoax or joke of some kind? The only reason I ask is that, when the blue screen appears, it does so in such a manner as to look extremely unlike an actual BSOD. It sort of "slides" in an animation from the side, not covering the whole screen. Any BSOD I've ever gotten on Windows 98 goes fullscreen instantly and "replaces" the whole screen rather than being a little window that "slides in".

Was this some sort of pre-release feature which they for some reason implemented but then removed? And if they faked/staged this, why would they do it in a way that looks so unreal the actual error screen?

5
  • 13
    Most likely an artifact created by the TV production equipment.
    – Brian H
    Apr 22 at 14:41
  • 2
    Because it's moving right along.
    – Ray
    Apr 23 at 10:59
  • Higher-quality version: <youtube.com/watch?v=yeUyxjLhAxU> Apr 25 at 10:07
  • Ah, I saw a BSOD in the middle of a Cirque de Soleil performance once. My wife worked for a much smaller operation in media and presentation and she knew her boss was present at the event too. For her, it was cathartic. Even the best can succumb to a BSOD!
    – RLH
    Apr 25 at 13:33
  • Hey, that's my old boss! Apr 25 at 16:45

1 Answer 1

50

VGA graphics and text modes have different scan rates.

The Windows desktop runs in some graphics mode (looks like 640x480, likely 60 Hz) while the BSoD is in text mode (720x400 at 70 Hz). The adapter used for splicing the VGA output into the live video needs to resync, causing this sliding effect. You can also see some flickering and graphics mode residue at the bottom of the screen, showing the adapter's difficulties to adapt (SCNR).

My theory is that the vertical scan change causes the entire input frame to resynchronize in a somewhat PLL style, with the horizontal adaptation causing this sliding/swiping effect. Quite possibly the VGA hardware also misses a few horizontal sync pulses, requiring a resync.

Incidentally, you can watch a much better version of the video here: https://www.youtube.com/watch?v=yeUyxjLhAxU

3
  • 22
    This is it. :) You can see these kinds of effects for yourself if you've used a TV or VGA capture card and plugged in cables. Also modern (relatively speaking, I'm talking about mid-to-late nineties) monitors and TVs that have onscreen displays have 'smarts' try to hide output that isn't synced up and stable as a nicety for the user, but older monitors didn't blank during adjustment, so between text/VGA 13h 70Hz/ModeX 60Hz, there'd be an audible 'twang' and the graphics region would slide into position as the electrical configuration would get accustomed to the new rates (caps charging etc)
    – knol
    Apr 22 at 14:48
  • Wouldn't that cause a vertical slide rather than an horizontal one?
    – jcaron
    Apr 25 at 11:57
  • @jcaron That depends on the actual implementation of the adapter - which we don't know sadly. The vertical misalignment is shown by the bottom residue though.
    – Zac67
    Apr 25 at 12:17

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