Graphics Card GPU Health Checks

(Page under development)

The checks here are for when the card has passed basic checks:

  • Acceptable resistances (especially PEX rail – if PEX is low the a dead GPU core should be suspected and the tests here can offer a scond opinion)
  • Acceptable voltages (All voltages are present, yet the card is not detected)

But the card is not detected in Windows Device Manager. In this case, when a card appears to be otherwise healthy it becomes a stronger possibility that there could be a GPU issue. This guide is intended to help test indicators of GPU health.


  • Multimeter
  • Oscilloscope (for BIOS and Crystal checks)

Areas to check

  • Check BIOS signals
  • Check data lanes
    • Transfer lanes
    • Receiver lanes
  • Check REFCLK+ and REFCLK-
  • Check crystal
  • GPU heat
  • PEX reset signal ()

For each add: what/how to measure, expected state, symptoms, implications

Example Cards