A customer brought in a machine last week with almost identical symptoms.  In her case, the graphics circuitry wasn't on a card, but embedded in the motherboard, with a take-off socket that was connected to the backplate plug by a ribbon cable.  

After disconnecting it and installing a PCI gfx card, the problem went away.

Ian Porter
Computer Guys Inc.
Arrowtown
New Zealand
[log in to unmask]

  ----- Original Message ----- 
  From: [log in to unmask] 
  To: [log in to unmask] 
  Sent: Friday, September 12, 2003 2:14 PM
  Subject: [PCBUILD] Overheating videocard?


  Dear Listers,

  Recently I've noticed some artifacting (discolored pixels in various areas of
  the screen).  The spots aren't the same, usually black dots while playing
  free cell or solitaire, and aren't necessarily in the same area all the time.  It
  would go away after a reboot only to appear after several minutes.  Now, when
  I reboot or cold start, right after the "press escape to enter setup" the
  boot screen is all scrambled.  There are letters and symbols all over the screen.
   The best I could describe it is like watching the starting scenes from The
  Matrix.

  I am able to boot to safe mode.  I removed the videocard and went to standard
  display adapter.  The artifacting went away but the boot screen was still
  scrambled.  Reinstalled videocard and adapter and couldn't boot to desktop - -
  the screen would remain black.  Only one control - alt - delete and the comp
  would reboot.  Artifacting wouldn't appear all the time, only in certain
  programs.  The windows screen will have five pairs of black vertical lines (almost
  like jail bars) covering it.

  I removed the case cover, air dusted the complete inside.  Left the cover off
  and cold booted.  Boot screen was still scrambled but not as much.  I could
  get to desktop after some delay.  I'm wondering if the problem is due to the
  videocard overheating? or, could the card be going?  I'm running Win98se on a
  2.4Ghz P4 512 Ram with a ASUS P4S8X mobo with an Asylum GeForce4 Ti4200
  w/128DDR.  No new programs/software has been installed except for Adaware updates and
  NAV updates.

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