Chip maker Intel today launched its latest desktop processor — the first in its Pentium 4 family to break the 3GHz speed barrier.

The new chip, which has a clock speed of 3.06GHz, is also the first Pentium 4 to feature HT ("hyperthreading"). Already built into its Xeon range of server processors, the technology allows multiple software threads to run more efficiently on a single processor.

"The thinking behind HT is that a huge amount of processing power is wasted by giving one gigantic chip a single set of instructions to process," said Robin Morris, senior reviews writer at PC Advisor.

"By making a virtual duplicate of the P4 chip and fooling the PC into thinking it actually has two processors onboard rather than one, HT can hand out tasks to 'both' processors at the same time," added Morris.

For users, the technology should translate into a performance benefit of up to 30 percent, according to recent presentations given by Intel executives> However, this also depends on whether support for hyperthreading is built into the operating system and software. Some versions of Linux and Microsoft's Windows XP support it, but earlier editions of Windows do not. Application software support is also limited.

But PC Advisor's first tests of the new chip were not that promising.

When we tested the Hi-Grade Ultis PV4 3.0GHZ HT we found the video encoding results were fantastic and faster than any other PC we had seen. But its low WorldBench score of just 118 was only improved (to 124) when we turned off the HT.

"In some cases, HT technology will cause the 'two' processors to get in each other's way. Intel's claim of 20 percent speed increases looks wide of the mark," explained Morris.