AMD's 45nm Phenom II Chips Overclocked To 6+GHz

CRN Staff

November 20, 2008, 07:43 PM EST

Advanced Micro Devices demoed its upcoming 45-nanometer "Deneb" desktop chips -- now confirmed as Phenom II -- for reviewers in Austin, Texas, on Thursday, and reports are in that AMD overclockers were able to achieve clock speeds north of 6 GHz on the second-generation quad-core devices.

How far north of 6 GHz? AMD spokesman John Taylor confirmed the basics of stories published by PC Perspective's Josh Walrath and Legit Review's Nathan Kirsch Thursday, but held back on outright endorsing the numbers originally cited in those stories.

Respecting AMD's wishes, we'll just point out that PC Perspective's story now says, "The Phenom II reached WELL over 5.x GHz (read: REALLY over)." And another source gives a more specific number -- 6.3GHz, though again, that could not be confirmed by AMD.

AMD, headquartered in Sunnyvale, Calif., reached such overclocking heights using liquid nitrogen to cool the processor that was taken to "WELL over 5.x GHz." PC Perspective reports that the Phenom II parts can also hit 4 GHz on air cooling and 5 GHz on dry ice cooling. The top Phenom II chip, due out sometime in the first quarter of 2009, will reportedly list as 3.0 GHz off the shelf.

Intel's top Core i7 processor, which incorporates the Santa Clara, Calif.-based chip giant's new Nehalem micro-architecture, is listed as a 3.2 GHz part. Overclockers have reportedly managed to scale it to 4.5 GHz on air cooling alone. Some enthusiasts have also taken Core i7s to 5.7GHz on liquid nitrogen, while the CRN Test Center conducted some "modest overclocking" on the Core i7-965 Extreme Edition to add some extra oomph to an already astonishing Geekbench2 score for that processor on an Intel "SmackOver" board.

AMD's Taylor said the Phenom II demos conducted Thursday were done on what the chip maker is calling its "Dragon" platform -- a quad-core Phenom II processor, ATI Radeon 4800 series discrete graphics and an AMD 790 chipset. Taylor said the processors shown were not hand-picked engineering parts, though he added, "But clearly they weren't duds."

Clock speeds for AMD's upcoming 45nm desktop chips appear to be mapping to the same sort of advantages the recently released 45nm Opterons code-named Shanghai have displayed over the previous generation of 65nm Barcelona server chips. Taylor said the extra level of "headroom" towards dramatic overclocking capacities on the Phenom II parts is due to a combination of architectural improvements over the original Phenoms first released late in 2007.

"It's about high-speed path optimizations, how it does memory pre-fetch, how it does branch predictions, the larger cache. So you've got higher clock frequency per TDP, but at the same thermals," he said.

"The result has been modest improvements on instruction per clock but much better clock frequency. It'll be the biggest step in processor improvement between generations that AMD has ever made, with the exception of leading the industry from single to dual-core."

So who said the clockspeed battles are over? Over the past few years, we've heard quite a lot about how it's not as important on multicore chips. But now that both Intel and AMD are really hitting their stride on successive generations of quad-core architectures, the new chips are coming out of the gate pretty darn fast.

Intel is hitting first with what it calls the "fastest processor on the planet" (with a lot of shared enthusiasm from reviewers, we should add) and the new Core i7 parts are, without a doubt, a major step-up in performance over the older Core 2 Quad chips. But AMD might just be about to drop some surprisingly powerful processors on the market as well.

"Phenom II is a big step up, too, but you don't have to open your wallet as wide to make that step up," Taylor said.