Stepping Back In Time For A New Champion
The Core i7-990X is a simply evolution of Intel’s six-core Gulftown design. It’s exactly the same architecturally—right down to family, model, stepping, and revision. These chips are binned higher to guarantee their stability at a base clock rate of 3.46 GHz and a maximum Turbo Boosted frequency of 3.73 GHz (when a single thread is active).
|Intel Core i7 Lineup (February 20, 2011 Price List) on www.intc.com|
|LGA Interface||Base Clock||Max Clock||Cores/Threads||L3 Cache||TDP||Price|
|Core i7-990X||LGA 1366||3.46 GHz||3.73 GHz||6/12||12 MB||130 W||$999|
|Core i7-980X||LGA 1366||3.33 GHz||3.6 GHz||6/12||12 MB||130 W||$999|
|Core i7-970||LGA 1366||3.2 GHz||3.46 GHz||6/12||12 MB||130 W||$583|
|Core i7-2600K||LGA 1155||3.4 GHz||3.8 GHz||4/8||8 MB||95 W||$317|
|Core i7-2600||LGA 1155||3.4 GHz||3.8 GHz||4/8||8 MB||95 W||$294|
|Core i7-960||LGA 1366||3.2 GHz||3.46 GHz||4/8||8 MB||130 W||$294|
|Core i7-950||LGA 1366||3.06 GHz||3.33 GHz||4/8||8 MB||130 W||$294|
|Core i7-880||LGA 1156||3.06 GHz||3.73 GHz||4/8||8 MB||95 W||$583|
|Core i7-875K||LGA 1156||2.93 GHz||3.6 GHz||4/8||8 MB||95 W||$342|
|Core i7-870||LGA 1156||2.93 GHz||3.6 GHz||4/8||8 MB||95 W||$294|
|Core i7-860||LGA 1156||2.8 GHz||3.46 GHz||4/8||8 MB||95 W||$284|
Though I’m sure you’re amply familiar with Intel’s Gulftown design and its underlying architecture, here’s a quick recap from Intel Core i7-980X Extreme: Hello, Six-Core Computing, remixed for today's review:
“Of course, Gulftown is enabled by Intel’s 32 nm manufacturing process—the same node we saw debut back in January of 2010 with the Clarkdale and Arrandale processor families. This time, however, enthusiasts don’t have to be bamboozled by a second, on-package 45 nm die handling graphics, memory control, and PCI Express connectivity. The Core i7-990X gets us performance-freaks back to where we want to be—on-die memory controller, PCI Express handled by the well-endowed X58 chipset, and discrete graphics only, please.
With Gulftown, Intel uses its 32 nm process to add cores and cache, rather than push integration. As a result, we have a six-core processor with 12 MB of shared L3 cache. Architecturally, Gulftown is otherwise the same as Bloomfield. Each core gets 32 KB of L1 instruction cache, 32 KB of L1 data cache, and a dedicated 256 KB L2 cache.
The 12 MB shared L3 actually is a potential performance-booster. Because the cache can be dynamically allocated, an application that only utilizes one core can conceptually monopolize the entire cache. According to Intel, there are some gains to be had in gaming, for example, but it’ll be difficult to gauge just how much of the speed-up we see comes from increased core count versus cache, particularly since we’re using very few single-threaded benchmarks any more.
Despite the addition of two cores and 4 MB of L3, Gulftown employs a smaller die than its predecessor (248 square millimeters versus Bloomfield’s 263). Transistor count increases from 731 million to 1.17 billion. That’s fairly incredible, considering the Core i7-990X fits within the same 130 W thermal envelope as existing Core i7-900-series processors.
Gulftown’s memory controller remains unchanged, still rated for three channels of DDR3-1066 memory. This is actually somewhat interesting, since the 130 W Westmere-EP processors support DDR3-1333 (and with up to two modules per channel, no less). Nevertheless, we should see similar memory performance, as Bloomfield’s four cores clearly weren’t starved for data anyway.
The other addition worth noting is AES-NI, Intel’s hardware-based instructions for accelerating the cryptography standard. Previously seen only in the company’s Clarkdale-based Core i5s (and unfortunately left out of the other Clarkdales), AES-NI isn’t yet having a massive effect on performance. But as we’ll see in the benchmarks, there’s a ton of potential there.”