Take it with a grain of salt but if the source is accurate the Radeon R9 470 will be based on the Baffin GPU (aka Polaris 11) and have a TDP of under 50W. The Radeon R9 480 on the other hand has an Ellesmere (Polaris 10) GPU with a TDP in the 110-135W range. Overall, this rumor is a bit strange:
The problem with this rumor is that it does not fit well with previous whispers that Polaris 10 would be powering the Radeon R9 490 series. So now we have two quite reputable sources claiming two different possibilities. However there is a chance that Polaris 10 is, in fact, used in both Radeon R9 480 series and R9 490.The VideoCardz article also republishes some preliminary leaked specifications of the Polaris 10 GPU “67DF:C4”:
Polaris 10 GPU “67DF:C4” Specifications (according to VR-World)
14nm FinFET, GlobalFoundries Diffused in USA (New York state) Assembled in Taiwan 2304 Cores (silicon: 2560) 36 Enabled Core Clusters (silicon: 40) New GPU Architecture (not GCN “1.5”) 256-bit Memory Controller 8GB GDDR5/GDDR5X (when available)