ATI Mobility GPU TDP

I've seen people say that the manufacturer's information sheet for the ATI cards only specify the power consumption of the chip itself, as opposed to the whole card including the memory, whereas NVIDIA specs would list the whole consumption. Is this true?

I was looking at the ATI specs for a card, and it said the following:

TDP: 30-39 Watts (GDDR5) or 31 Watts (GDDR3/DDR3)

ATI Mobility Radeon? HD 5850 GPU Specifications

Would those values be including the memory then?

 

Maybe includes memory, but definitely not PCB, so it's definitely not going to be the total TDP of the card.

 

It does include the memory which you proved yourself with a quote from ATI specs.
The same goes for other similar cards like 5730 and 5770- it's the same core but the latter has GDDR5 instead of GDDR3 and TDP between the two differ because of this.
As for PCB- it doesn't include it and there's a reason for it- some cards are MXM but most are integrated into the mobo so it would be rather pointless plus the difference would be insignificant.

 

It's also possible that the TDP doesn't actually include memory, while the difference in TDP is in fact due to the memory controller in the GPU - after all, the memory controller has to work much harder to handle GDDR5's doubled bandwidth per clock and higher clock speeds. That idea is supported by the temperature typically being significantly higher for MemIO than for the rest of the GPU on these cards.

In any case, I've seen benchmarks that suggest ATI's mobile cards consume more than their TDP would suggest, so something has to make up the difference, and I'm not sure the PCB alone would explain it.

 

I see, so NVIDIA cards include the whole thing?

 

On the whole, TDPs are generally very poorly defined figures, and the best you can get out of them is a rough indication of how two different components from the same manufacturer compare.

Nonetheless, here are some power consumption figures for a W860CU with a 5870 vs a 285M. Don't look at the idle figures too much, since by default the 5870 doesn't downclock in the W860CU when idle; this can at least be fixed by manually downclocking. Plus, TDP has no bearing on idle power consumption.