Question What gpu does tdp really mean?

[hephaistos]

What does a gpu's tdp really mean? Does it mean the amount of wattage it picks up from the psu, or the amount from the pcie slot or both of them? Did my GTX 950 draw 90 watts separately from the power supply or was that only 15w and 75 with the pcie slot. Could somebody pls educate me? Also are the values for recommended power supplies accurate or no? Because the gtx 970 recommended psu wattage is 500 however heard that it even runs on a quality 450w psu. Also where does the gpu pick up the power from? The 12V rail? What does the 3.3V and the 5V rail do? Any help guys?

 

[Zephyl]

TDP is the maximum heat measured in watts that a processor produces. Power draw is completely separate from this measure, and is always more. The 950 uses 170 watts total, in practice, 75 of which would be from the slot.The GPU (and CPU) draws almost exclusively from the 12V rail. The other rails are for other things like the RAM, other expansion cards, motherboard functions, among others.

 

[hephaistos]

TDP is the maximum heat measured in watts that a processor produces. Power draw is completely separate from this measure, and is always more. The 950 uses 170 watts total, in practice, 75 of which would be from the slot.The GPU (and CPU) draws almost exclusively from the 12V rail. The other rails are for other things like the RAM, other expansion cards, motherboard functions, among others.

So when the tdp of a gtx 480 is 600w it means that 600w power is heat. When a cooler is 150w tdp it means it cools 150 watts? So the tdp is the wattage wasted on heat energy? Sorry if I don't rly get this?

 

[ko888]

A reference design NVIDIA GeForce GTX 480 card only has a TDP of 250W.

A minimum of a 600 Watt or greater system power supply with a maximum combined +12 Volt continuous current rating of 42 Amps or greater and with at least one 6-pin and one 8-pin PCI Express supplementary power connectors was NVIDIA's recommended PSU specs.

 

[Metal Messiah.]

https://linustechtips.com/main/topic/453630-graphics-card-tdp-and-power-consumption-explained/

https://www.geeks3d.com/20090611/tutorial-what-is-the-thermal-design-power-tdp/

 

[Zephyl]

So when the tdp of a gtx 480 is 600w it means that 600w power is heat. When a cooler is 150w tdp it means it cools 150 watts? So the tdp is the wattage wasted on heat energy? Sorry if I don't rly get this?

No, a 600W power supply is recommended for the 480. As ko888 said, its TDP is 250W, and according to NVidia, so is its maximum power consumption. The TDP is not wattage "wasted," but it's wattage that has run through the processor and has been converted into heat energy as a by-product.