2000: Rambus Still Slow to Roll

The next generation of random access memory technology is up and running on high-end PCs, and 2000 figures to be a year of growing popularity for Rambus Dynamic Random Access Memory.

But RDRAM likely won't hit mainstream desktops until late next year, as PC makers continue to prefer Synchronous Dynamic Random Access Memory. "I think SDRAM is as strong next year as it is this year," predicts Kevin Knox, a research director with the Gartner Group.

RDRAM helps remove a bottleneck for today's superfast processors from Intel and Advanced Micro Devices, which now topping 800 MHz and are expected to exceed 1 GHz next year. Pushing data over 100-MHz SDRAM memory buses limits performance. Chip designers have tried to alleviate the bottleneck with secondary memory caches, but those are now producing diminishing returns, especially with large graphics files, says Subodh Toprani, senior vice president at Rambus, the company that developed and licenses the technology.

RDRAM uses a new bus and chip architecture to run memory operations much faster, currently at 800 MHz, which allows transfers on the memory bus of up to 1.6 gigabytes per second--twice as fast as in conventional SDRAM systems.

RDRAM accounts for performance boosts of around 10 percent in AutoCAD and up to 20 percent in Adobe Photoshop, according to benchmark tests cited by Toprani. But Knox says that although RDRAM has some immediate speed advantages, today's chips run fine with SDRAM, and real bottlenecks won't appear until next year's leap to 1 GHz.

The bottom line: RDRAM's performance improvements won't be noticeable to the average user.

You Get What You Pay For

In part due to Rambus licensing fees, RDRAM is still about twice as expensive as SDRAM.

So for most users SDRAM will remain the memory of choice, bolstered by modest performance improvements in next-generation systems with 133-MHz memory busses. Memory capacities, meanwhile, are likely to stay at 128MB, with the highest-performance systems sporting 256MB, Knox says.

Game Enough for You?

RDRAM hit a serious speed bump this fall when bugs in Intel's supporting 820 chip set caused some PC makers and even Intel itself to hedge their bets with stepped-up PC133 efforts.

Still, RDRAM has made inroads into consumer electronics. Sony's PlayStation2 game console uses dual-channel RDRAM that can run at 1.6 GHz. Next year digital televisions, records, and set-top boxes will incorporate the chips for faster MPEG-2 decoding.