Does unused pci slots draw power from psu?

[Thineshwar]

will unused pci ports draw power frm psu?i wanted to calculate the power consumption for my pc..........

 

[Muzzammil22]

Power Supply Calculator


Enter all your pc specifications and see for yourself and as for unused pci slots they draw power but that drawn power is not utilised since no load (graphics card) is connected to use psu power.

 

[Wolfshadw]

The expansion slots draw minimal power, if any at all, when not populated. Regardless, you don't want to be so close on power limitations that you would even be concerned about that. Look at the chart below for graphic cards:

Power Connections/Max Wattage
None/75 watts
1 6-pin PCI-E/150 watts
1 8-pin PCI-E/225 watts
1 6-pin + 1 8-pin PCI-E/300 watts
2 8-pin PCI-E/375 watts

Depending on the number of power connections your graphics card has, take the maximum wattage listed and add that to the Thermal Design Power (TDP) of your processor. Add 30% on top of that and you will have more than enough power for your system.

Example:

Your processor has a 95 watt TDP.
Your graphics card has one 6-pin PCI-E + 1 8-pin PCI-E power connector.
The sum of these two is 395 watts.
Add 30% to get to 513.5 watts.
Any quality power supply in the 520 to 650 watt range should be more than enough for the system.

-Wolf sends

 

[ko888]

will unused pci ports draw power frm psu?i wanted to calculate the power consumption for my pc..........

No. Unused slots don't present a load to the PSU unless there is a short circuit in the slot.

 

[shrapnel_indie]

Empty PCIe slots, just like all expansion slots before them, will not draw any power (current/amps/amperage/watts/wattage) when there is nothing using them. Now, any PCIe lane switches that may exist will draw power, but are considered part of the power draw of the motherboard itself.
Voltage is another story as it will always be present used or unused. However voltage doesn't count in empty sockets or connectors when not in use.