Amd strikes back.(AMD Athlon XP 1800+ and Polywell Poly 880XP-1800 microprocessors)(Evaluation)

PERFORMANCE and controversy mark AMD's new Athion XP.

The XP chips (XP stands for "extreme performance" and has no relation to Microsoft's Windows XP) debut at speeds that range from 1.33 to 1.53 GHz, but they're labeled according to a rating system that, AMD says, more accurately reflects the chips' performance. The new scheme is part of AMD's fierce baffle to end the megahertz myth-- namely, "The more the megahertz, the better the PC." It's the biggest marketing gamble AMD has taken in some time.

But regardless of whether this chip naming system pays off, the first Athlon XP machines seem top-notch.

In our tests of two pre-production systems based on the Athlon XP 1800+ (1.53-GHz) chip--the $2750 Polywell Poly 880XP-1800 and the $3049 Xi 1800+ MTower SP-both PCs outperformed a comparably configured 2-GHz Pentium 4 Dell machine (priced at $2919) on our PC WorldBench 2000 business-application tests and on several other measures.

Savvy PC shoppers already know that megahertz ratings don't reveal which processor makes a PC run fastest: Not until Intel pumped the P4's clock speed to 2 GHz did business systems using the P4 match the performance of PCs using the 1.4-GHz AMD Athlon, on most jobs. And if you're shopping for a high-end desktop PC today, you definitely have more than megahertz to consider. Looking ahead, Intel will also soon roll out some highly anticipated new P4 chips. However, analysts say that now--and even in the coming months--most value-and performance-minded buyers will find AMD Athlon XP PCs tough to beat.

INSIDE XP RATINGS

THE ATHLON XP processor uses the same chip core, code-named Palomino, found in Athlon 4 notebook chips. An XP CPU uses about 20 percent less power than the original Athlons and boasts design changes that speed information to waiting applications. It also has 3DNow Professional, which adds 52 new 3D and multimedia instructions and makes it compatible with Intel's SSE instructions.

Some Athlon XP systems may get a boost from NVidia's new NForce system chip set (see "May the NForce Be With…