Yesterday Intel made a lot of noise about its new low-power Ivy Bridge Core processor line. It claimed that the new chips are far more power-efficient than the current low-voltage CPUs, proudly touting that they drew as little as 7W. All is not what it seems, however, as Ars Technica has taken an exhaustive look at Intel's claims, revealing a classic bait-and-switch from the chip giant. The issue stems from the figure Intel is quoting in its "7W" claim — SCP, or "scenario design power" — an entirely new term that benefits intel's marketers more than it benefits us. In the past, the company has always quoted its chips' power efficiency in terms of TDP (thermal design power), a figure that reflects the amount of cooling your processor requires when running at 100 percent. SCP, however, refers to the power draw of a chip in "average" conditions — the two figures are not really comparable.

What seems like a 10W power saving is in most cases only 4W

Examining Intel's full lineup from yesterday's announcement reveals a far less impressive set of power-savings across the board. Most of the "7W SCP" processors actually have a TDP of 13W, with the 1.1GHz Pentium 2129Y the only chip to reach the 10W power draw Intel promised last month. When compared to the 17W TDP of prior low-power Ivy Bridge processors the new chips should help extend the running time of devices, but Intel has only managed to achieve that saving at the expense of computing power. Intel has reduced both the running and turbo clock speeds when compared to current processors, and although it may have changed other things, the new chips will definitely not be as powerful as the outgoing line.

Intel's tactic isn't even new

Intel's tactic of lowering clock speeds to save battery life isn't new — Asus's Zenbook Prime included an option to lower the power draw of its Core processor from 17W to 13W: it's a feature of Intel's low-power Ivy Bridge platform. So, it's clear that Intel hasn't been upfront about the abilities of its new processors, but what does that mean for users buying a new laptop or tablet with one of the chips? Ivy Bridge is and has always been a very capable platform, so cutting its power won't impact overall performance too negatively. That said, even though the average power draw may be lower, manufacturers will still have to allow for space to cool the maximum TDP, rather than Intel's newly-invented, lower SCP figure. That means we're unlikely to see dramatically thinner laptops and tablets because of the so-called "7W" chips.

We reached out to Intel for comment on its new Ivy Bridge processors and will update the article when we hear back.