AMD has, as expected, announced its plan to tackle arch-rival Intel's dominance of the netbook arena. But its efforts will centre on a new CPU: a 45nm dual-core part dubbed 'Conesus'.

Due sometime next year, Conesus contains 1MB of L2 cache - 512KB per core, presumably - and a DDR 2 memory controller. That broadly matches the spec of its rumoured UMPC CPU, 'Bobcat'.

Conesus, like its 2010 and 2011 successors 'Geneva' and 'Ontario' - the latter a 32nm part - are primarily aimed at "ultra-portable" laptops - kit like Apple's MacBook Air and Toshiba's Portégé R600 - but AMD's roadmap shows them stretching down into the "mini-notebook" - ie. netbook - space too.

Expect netbooks to use a single-core variant of Conesus, currently codenamed 'Huron'. Huron is part of AMD's 'Yukon' platform, which pairs the CPU with the company's RS690E northbridge and SB600 southbridge. Higher-end ultraportables will use 'Congo', which is Conesus plus the RS780M and SB710.

Come 2010, both will be superseded by 'Nile', which connects Geneva to an as-yet-unspecified chipset.

AMD said Yukon is due H1 2009, which narrows the release window for Conesus and, presumably, Huron too. With Intel expected to launch a dual-core successor to the mobile Atom N270 chip next summer, the room for a single-core rival is narrowing all the time.

Interestingly, there appeared no mention of Bobcat at AMD's analysts meeting last night, which lends weight to earlier claims that it cancelled the chip. AMD denied that, but it's clear that while it may well have knocked Bobcat off the roadmap, it has added a replacement.

Yukon will have a "sub-25W TDP", AMD said, which puts it well up on Atom (2.5W) even if you take into account the chipset Atom usually comes with (6W). The single-core Huron will consume less power than Consesus, but even so, AMD's going to be struggling to get its overall TDP down to Atom levels.

That suggests AMD's focus is far more on slim but powerful systems than it is on compact but lightweight netbooks. Small Computers, yes - but not necessarily Small, Cheap Computers.