Editing Nvidia Pascal GPU Diagnosing Guide (section)

== Step 1: Base Voltage Rails (12V, 3.3V) ==
The base voltages are the ones that get supplied to the card through the motherboard and the external 8pin power connector(s). [[What are the Base Voltage rails for GPUs?]]

=== 12V rails ===
The card gets supplied 12v through the PCIe slot and additional 6-8 pin connector(s)

Start by measuring the resistances of the 12V rail coming from the PCIe slot (first 3 pins, see figure 1). 

After that, measure each inductor for external power connectors (some cards have multiple external power connector and each of them have their own inductor you have to measure each of them individually).

The resistance varies from card to card and the value itself doesn't matter but it should be in the thousands+ Ω range. If you get 50Ω or less then you most likely have a short on the card.

Solution: Check out this page dedicated to [[Base Voltage Rail Short on Pascal GPUs]].

=== 3.3V rail ===
The card gets 3.3V from the PCIe slot only, from the 4th pin going left from the PCIe key notch in the front, and 2nd and 3rd pins on the back going from the notch again.  

If you get less than 50Ω on one or multiple base rails then you have a card with a short. The computer might not turn on in such a case because the power supply is protecting itself using OCP (over current protection). 

Solution: Check out this page dedicated to [[Base Voltage Rail Short on Pascal GPUs]]. 

Otherwise, if you have no short then you can continue troubleshooting.