The holiday-time chip battle continues to heat up with AMD's launch yesterday of its Athlon XP 1900+ processor.

The Athlon XP 1900+ is the latest chip to carry a model number based on AMD's controversial naming scheme that looks at performance instead of pure megahertz.

The 1900+ chip's actual frequency is 1.6 GHz. Eventually the current model-numbering scheme will give way to an industry-wide rating AMD is spearheading called, it seems almost oxymoronically, the True Performance Initiative, said a spokesman. [the spokesman said it was an oxymoron? I doubt it hardly…]

Among the first vendors expected to ship PCs powered by the chip are MicronPC, HP and Compaq.

This model numbering system is designed for the end user who doesn't understand that a one 1.5GHz chip can run differently to another 1.5GHz chip, says Mark de Frere, AMD's Athlon brand manager.

In lay terms, this is like two car manufacturers selling 1.6l-engined cars but with different weights, handling and gear ratios. AMD is desperate to drum into consumers that pure processor numbers aren't everything, probably in part because it cannot match Intel on that basis.

The launch is just the latest in the ongoing skirmish between Intel and AMD. Recently, the two have been going back and forth slashing prices in an effort to stimulate the slumping PC industry's holiday sales.

With this launch, AMD makes things more interesting for Christmas shoppers with a chip that one analyst predicts will compare favourably to Intel's 2GHz Pentium 4.

While de Frere is ready to declare the model number system a success, analyst Dean McCarron of Mercury Research says it's too early to tell if the system will fly. However, the initial response hasn't been bad, he says. "We haven't seen any wholesale rejection, which was the main concern."

The important thing about the model numbers is it helps AMD compete with Intel and its high-revving P4. Despite the P4's higher speed, benchmarks continue to show the 'slower' AMD chips keeping pace.

McCarron says he's been impressed with AMD's restraint when naming its new chips. While AMD claims the processor numbers merely represent performance compared to previous Athlon chips, everyone knows the company wants it compared to the P4.

"The testing that we've done has been more than consistent with the number they're putting on it, assuming they're pitting it against the P4," he says.

"I think they could have named the 1800+, the 1900+," McCarron adds. "It just illustrates how careful they are being." AMD uses an outside firm, Anderson, to audit its benchmark results for authenticity.