During its CES press conference, Intel introduced a new family of 7W Ivy Bridge chips. The specifications for these Y-series processors have made their way onto the web, and you might be surprised to learn that all the Core-based models have 13W TDP ratings. 7W refers to the Scenario Design Power, or SDP.
According to Ars Technica, SDP isn't really a new thing; it's a previously unpublished power rating that refers to sustained, heavy workloads rather than short bursts of activity. Intel won't publish SDP figures for its other mobile processors, according to the site, leaving plenty of room for confusion. Fortunately, the other specifications for the Y-series CPUs are pretty clear:
|Model||SDP||TDP||CPU clock||GPU clock||Cores/
The processors have relatively low base CPU clock speeds, which they'll supposedly be able to sustain even under heavy loads. However, the Turbo-equipped Core i5 and i7 variants may ramp up less aggressively than Intel's other mobile chips, and they won't peak as high. Intel's HD 4000 integrated graphics also takes a hit with the Y-series parts. Although the base 350MHz clock speed hasn't budged, the maximum speed is capped at 850MHz, down from 1.05-1.15GHz in 17W Ivy Bridge CPUs. I'd expect the IGP's dynamic frequency scaling to be more conservative, as well.
Referring to Y-series processors as 7W parts is a little disingenuous, and it seems unnecessarily convoluted to use SDP ratings for some CPUs and TDP for others. To Intel's credit, the TDP ratings for the new chips are at least being published alongside the SDP figures.