Sandy Bridge-E Explained
Sandy Bridge-E, and by extension the Core i7-3960X Extreme Edition, has a lot in common with the Sandy Bridge microarchitecture, which arrived earlier this year with the Core i7-2600K and other members of the second generation Intel Core processor family—it’s just bigger and badder. As such, we won’t be rehashing many of the details again here, but we would suggest checking out a few previous articles if you’d like more details regarding Intel’s Turbo Boost Technology 2.0, Smart Cache, and Smart Response Technology.
- Intel Core i7-2600K and i5-2500K Processors Debut
- Intel Core i7-2820QM Mobile Sandy Bridge Processor
- Intel Z68 Express with Smart Response Technology
In our Core i7-2600K and Core i5-2500K launch article, we go in-depth on the Sandy Bridge microarchitecture and cover many details that are pertinent to today’s launch as well. In our Core i7-2820QM coverage, we outline more architectural details and in on our Intel Z68 Express with Smart Response Technology article, we detail Intel’s SSD caching technology, a.k.a SRT.
Intel Sandy Bridge-E Die Map
As we’ve mentioned, Sandy Bridge-E shares many of the same features of the Sandy Bridge microarchitecture, but as the “E” denotes, SBE is more extreme. What you see pictured above is a die map of a Sandy Bridge-E based Core i7-3960X Extreme Edition processor. The chip is manufactured using Intel’s advanced 32nm process node and features roughly 2.27 billion transistors. The die size is approximately 434.7mm2 (20.8 mm x 20.9 mm).
The initial batch of processors based on the Sandy Bridge-E microarchitecture will feature 6 active execution cores that can each process two threads simultaneously courtesy of Intel’s Hyper-Threading technology, for support of a total of 12 threads. Although, you’ll notice in the die map that there are actually two cores dormant in the chip. The die actually has eight cores, but due to power and yield constraints with the current revision, only six are active at this time. We asked when / if an 8-core SBE would ship and were of course told that Intel doesn’t comment on unreleased products, but you can bet the farm they’ll be coming at some point. The actual cores are essentially identical to the original Sandy Bridge microarchitecture and support the same Intel AVX and AES instructions, along with SSE4.1, SSE4.2, etc.
Sandy Bridge-E based processors like the Core i7-3960X Extreme Edition are designed for a new socket, LGA 2011, and require a compatible motherboard built around the new X79 Express chipset (more on that later). The processors will support up to 15MB of shared L3 Intel Smart Cache, although there is actually 20MB on die (the remaining L3 is disabled along with those other two cores), and feature integrated quad-channel memory controllers with official support for DDR3 memory at speeds up to 1600MHz, although higher speeds are possible through overclocking.
Sandy Bridge-E based processors also feature 40 integrated lanes of PCI Express connectivity, that support speeds equivalent to the 8GT/s PCI Express 3.0 specification. Intel won’t be designating the lanes as PCIe 3.0 compliant at this time, however, because the company has been unable to qualify them with the necessary PCIe 3.0 compliant add in boards, which don’t exist just yet.
The Intel Core i7-3960X Extreme Edition processor we’ll be featuring here today has a base clock frequency of 3.3GHz with a maximum Turbo frequency of 3.9GHz. It achieves those clocks using a BCLK of 100MHz (mistakenly labeled bus speed in the image above) and multipliers ranging from 33 to 39, although lower and higher multipliers are available with this unlocked processor. The chip sports 192K of L1 data cache (32K per core), 192K of L1 instruction cache (32K per core), and 1.5MB of L2 cache (256K per core). The Core i7-3960X Extreme Edition is also outfitted with 15MB of shared L3 cache, although lower-end variants of the chip will have 12MB (or potentially less).
The chip has a 130W TDP similar to Intel’s current high-end Gulftown-based processors and has a .95 to 1v base input voltage, although that voltage will automatically scale upwards when higher multipliers are used, when Turbo Boost frequencies kick in, for example.