It has become clear that Intel didn't want to waste much time before following-up on its initial Core M lineup, because despite those first chips dropping just a couple of months ago, the company has added 4 more to its roster. Like the launch chips, these four are dual-core designs that support HyperThreading to enable an effective four threads for processing. Also like those earlier chips, these are spec'd with a TDP of 4.5W. Given these similarities, what's actually new about these chips?
For starters, these new chips are generally faster than the launch models, with a new top-end SKU called the M-5Y71. This chip has a base clock speed of 1.2GHz, but is burstable through Turbo up to 2.9GHz. While it would have been nice to see the 3GHz mark reached, we didn't quite get there.
What really sets these chips apart from the initial Core M models is that their TDP is scalable, based on what the builder is looking to do with it. If the chip is set to be used in a notebook with very little free space, the OEM could opt to drop the chip down to 3.5W and lose 600MHz in the process. By contrast, a bulkier notebook could handle a hotter chip better, so a higher TDP could be decided upon. If that route's taken, any one of these new chips could peak at 6W and add 200MHz to the clock. That'd put a chip like the M-5Y71 at 1.4GHz, rather than 1.2GHz.
Another perk that's pretty easy to overlook is a boost to the graphics. The IGP in the initial Core M chips were clocked at 100MHz base, while these new CPUs start off at 300MHz. Likewise, the top-end clock for the top two models can reach 900MHz, whereas some of the launch models peak at 850MHz. It's really pretty impressive that with a chip like the M-5Y71, Intel managed to boost not only the CPU (by 300MHz with Turbo), but also the GPU, and still retain that 4.5W TDP.
According to Intel's ARK, all four of these new models have officially launched, but given the timing, this holiday season is going to be missed. Instead, they'll hit the market in early 2015.
I wonder where Braswell will fit (successor to Bay Trail). Some will be quad core. Laptop version Bay Trails have 7.5 W TDP so I wonder if they increase performance for the same TDP or drop the TDP. Graphics will be better, but it's still unknown by how much.
Those 6W core-M will likely be limited by "Configurable TDP" in some/many(?) devices, especially when they get hot or on battery (and fanless gets hot easily).