Graphics Cards: TDP and TGP (and don’t forget TBP, GCP and MPC…)




Graphics card power connectors

 
Looks like upcoming Radeon RX 5700 graphics cards do not leave the creator of GeForce GPUs indifferent, because NVIDIA has reacted by publishing this slide showing the power consumption of some GeForce vs Radeon cards:


GeForce and Radeon TDP and TGP
source

 
Power consumption is a term a bit vague because NVIDIA uses acronyms like TDP (widely used in the world of graphics cards) and TGP to talk about the power required by the graphics card.

  • TDP: Thermal Design Power (or Thermal Design Point or Thermal Design Parameter)
  • TGP: Total Graphics Power
  • TBP: Total Board Power (or Typical Board Power, used by AMD)
  • GCP: Graphics Card Power
  • MPC: Max Power Consumption

 
The TDP is the maximum amount of heat generated by the graphics card that a cooling system has to dissipate (the power is dissipated in the form of heat) under normal conditions (?). For example, a TDP of 100W means the VGA cooler must be designed to dissipate heat equivalent to 100W. The TDP does not reflect the total power consumption of a graphics card.

At the same time, the TDP acronym is widely used to define the (total) graphics card power… But now, it seems it has a new meaning: according to the slide, TDP is the GPU power only (that could explain why NVIDIA calls it Thermal Design Parameter and not Thermal Design Power). Are “Thermal Design Parameter” and “Thermal Design Power” the same thing?

The power consumption of the whole graphics card is defined by the TGP or Total Graphics Power (or TBP for Total Board Power or Typical Board Power in AMD’s GPU specs…). This is interesting because we have a new information: the difference between the TGP and TDP which represents the power consumption of graphics memory sub-system + the power consumption of the power circuitry (VRM) itself. Looks like Radeon cards have less power loss than GeForce ones (30W for the RX 5700 against 45W for the RTX 2060)…

The definition of the TGP from Quadro-Power-Guidelines.pdf:

The TGP (total graphics power) represents the maximum amount of graphics board power that the system power supply should be able to provide to the graphics card.

NVIDIA also uses the term Max Power Consumption (MPC) in the specifications of some cards like Quadro RTX. The MPC is not equal to the TGP as we can see in one of NVIDIA’s papers (Quadro-Power-Guidelines.pdf). For example, the TGP of the Quadro RTX 5000 is 230W (in the pdf paper) while the MPC is 265W (on the website). But there is no mention of the GPU power (TDP) of the RTX 5000… I think the MPC is max power consumption supported by the graphics board without damaging it while the TGP/TBP is the max electrical power consumption of the whole graphics card under load (still under normal conditions). And for sizing / security reasons, MPC > TGP.

In the specs of the Quadro RTX 8000, NVIDIA specifies the power consumption using Total Board Power (295W) and Total Graphics Power (265W). For Quadro cards, Total Board Power is not Total Graphics Power. Total Board Power is rather equivalent to Max Power Consumption.


Quadro RTX 8000 power consumption

 
On this page (updated yesterday…) the power consumption of GeForce and Quadro cards is referenced by TBP (the total power of the board) but someone forgot to update the tooltip which still uses the term TDP to explain the TBP. Quel bordel!

The TDP is used in place of Total Board Power in the Turing architecture whitepaper:


TDP in Turing whitepaper

 
The important value is the total board power (or graphics card power draw) because it shows the total electrical power required by the graphics card (PCI Express slot + 6/8 pins power connectors) when the graphics load is high. This power allows to select the right PSU and has an impact on your electrical bill…

In next graphics cards specifications, I will try to use the total board power (TGP/TBP) in place of TDP since the TBP is, most of the time, the only value given by GPU makers. And the total board power is more or less the value we can measure during graphics cards reviews.

Here is a table that tries to list the total board power consumption (TBP) and GPU power of some recent cards. I will update this table as soon as I get new values.

Graphics Card Total Board Power
(in Watts)
GPU power
(in Watts)
Delta power
(in Watts)

GeForce

Titan RTX 280
GeForce RTX 2080 Ti 250
GeForce RTX 2080 215 148 67
GeForce RTX 2070 FE 185
GeForce RTX 2070 175 120 55
GeForce RTX 2060 160 115 45
GeForce GTX 1660 Ti 120
GeForce GTX 1660 120
GeForce GTX 1650 75

Radeon

Radeon RX 5700 XT 225 180 45
Radeon RX 5700 180 150 30
Radeon VII 300
Radeon RX Vega 64 295
Radeon RX Vega 56 210
Radeon RX 580 185
Radeon RX 570 150
Radeon RX 560 60-80
Radeon RX 480 150
Radeon RX 470 120
Radeon RX 460 70

Quadro

Quadro RTX 8000 260
Quadro RTX 6000 260
Quadro RTX 5000 230
Quadro RTX 4000 125
Quadro P6000 250
Quadro P5000 180
Quadro P4000 105
Quadro P2000 75
Quadro P1000 47
Quadro P620 40
Quadro P400 30

 

References





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