CRT:IBM 8503

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IBM 8503
Olivetti PCS 286 - HP LaserJet 4L - Nan Tan Computer KB 6252E A - IBM 8503.jpg
Manufacturer Tatung
Type Business
Size 12"
Regions See text
240p/480i No
480p Yes
720p No
Vsync 60/70 Hz
Widescreen No
Component 1x HD-15 (VGA, fixed cable) Y/H/V
Earliest Date 1987
Latest Date > 1989-9
Brochure [1]

The IBM 8503 Personal System/2 Monochrome Display is the original VGA (and 31 kHz VGA only) black and white monitor, along with its premium color equivalent - the 8513.

As to IBM tradition, the full model number (MT/M) is made of a 4-character family (8503) and a 3-character specification, here indicating input mains voltage (001 is North American spec, 002 European, ...)

It runs somewhat hot due to the large resistors used in the linear power supply; electrically, however, it's a cold chassis design using a full size isolation transformer (after the socket, switch, and fuse). The high voltage connector is made of somewhat hard clear plastic which tends to retract over the years, leaving a gap for dust to get into.

It pre-dates DPMS and EDID, and does not have any OSD except for a test pattern (white screen with uncontrolled height if pin 5 is not grounded). Unused pins are not present, making it compatible with sockets that have pin 9 filled. For best compatibility with sources that do not expect such a display, an EDID & channel mixer box is desirable.

Flyback: TFB-648E, secondary 18 kV


As factory configured, the image is significantly underscanned.


  • Power, Brightness (with 50% stop), Contrast


  • Centering, Geometry (magnetical)
  • H/V Size
  • Static and Dynamic focus
  • Video gain (sub contrast), on neck board