P4 Bests Athlon

Fast Bus, Same Fare

System chip sets--the unglamorous supporting characters on a motherboard that keep a PC's show running--continue to be a key part of an informed buying decision, and in some ways Intel's newest chip sets differ significantly from their predecessors. Among four new chip-set options, you'll find some with built-in support for USB 2.0 and others with Intel's latest integrated graphics.

The new 850E chip set (replacing the 850) ships only on P4 systems with PC 800 RDRAM memory. This chip set supports both the new 533-MHz frontside bus and the older 400-MHz bus, but doesn't bundle USB 2.0 support or integrated graphics. Since RDRAM ships in only the most expensive of today's high-end systems, few buyers would want integrated graphics anyway. However, the lack of integrated USB 2.0--the new standard that over-optimistically promises speeds of up to 480 mbps compared with 12 mbps on the older USB 1.1 standard (see "USB 2.0's Real Deal," April)--means that vendors must spend a little more to add this feature separately.

Intel's 845E and 845G chip sets (replacing today's 845) are the ones you'll see in most mainstream PCs. These work with DDR memory (alternatively, vendors can choose PC-133 SDRAM for the 845G) and include support for USB 2.0. Both also support the P4's 400- and 533-MHz bus.

Better Graphics

The 845G chip set differentiates itself by offering Intel's latest integrated graphics technology, which saves the PC maker the cost of a separate graphics card--a savings they generally pass along to buyers. But because this chip set also supports a separate AGP 4X graphics card, a PC vendor--or buyer--can add such a card later.

Intel compares the graphics power of the 845G chip set to that of an older, mainstream graphics processor, the GeForce2 MX200. Although the gaming and graphics crowds have moved to more sophisticated and expensive graphics cards based on chips such as the GeForce3 and GeForce4, Intel is betting that the 845G will deliver enough graphics power to satisfy cost-conscious middle-of-the-road PC buyers.

The 845G systems use what Intel calls Dynamic Video Memory Technology. In previous integrated-graphics systems, the Intel processor claimed a chunk of the system's main memory for graphics use. In the new scheme, software applications and Intel's graphics driver software can have on-the-fly conversations with the operating system to discuss how much system memory should be dedicated--up to 48MB--for a graphics processing chore.

The final new chip set, the 845GL, appears in Celeron systems only. It has the same integrated graphics technology as the 845G, but with no graphics card upgrade path.

Most PC vendors will phase out the older chip sets in favor of the new ones relatively quickly, but if you want to ensure that you get the latest technology, check before you buy.

Also, Intel isn't charging anything extra for the new chip sets, so don't let a PC vendor charge you a premium for a PC that uses one.