Intel has rolled out four Mobile Pentium 4 processor that finally bring its HyperThreading technology to notebook computers, though the chips' frontside bus has yet to exceed an effective bit rate of 533MHz.

It also shipped a new Celeron desktop chip, taking the family to 2.7GHz.

The four chips are clocked at 2.66, 2.8, 3.06 and 3.2GHz, dropping to 1.6GHz when Intel's SpeedStep power conservation technology is in full swing. Each chip has a "target" average power consumption of under 3W, but clearly mileage will vary according to use. Full out, their core voltage is set to 1.55V - or 1.2V when SpeedStep knocks it down.

In any case, all four processors are aimed at desktop replacement notebooks where long battery life is arguably less of an issue, and most users will be operating their processors at full whack on mains power.

HT will provide a small performance boost on multi-threaded applications, including Adobe Premiere, Unreal 2 and Windows XP itself. Intel claims over 100 desktop apps are already multi-threaded and thus ready to take advantage of HT. But there are still plenty that aren't, however.

Each chip contains 512KB of on-die L2 cache, and operate across a 533MHz FSB. They are backed by Intel's 852GME and 852PM chipsets.

Prices for the parts, in batches of 1000 chips, are $653, $433, $294 and $234, for the 3.2, 3.06, 2.8 and 2.66GHz parts, respectively. However, it's worth remembering these prices are expected to fall in a month's time, on 26 October.

The 2.7GHz Celeron costs $103. ®