Sandy Bridge is manufactured in the 32 nm process and has a soldered contact with the die and IHS (Integrated Heat Spreader), while Intel's subsequent generation Ivy Bridge uses a 22 nmdie shrink and a TIM (Thermal Interface Material) between the die and the IHS.
Sandy Bridge retains the four branch predictors found in Nehalem: the branch target buffer (BTB), indirect branch target array, loop detector and renamed return stack buffer (RSB). Sandy Bridge has a single BTB that holds twice as many branch targets as the L1 and L2 BTBs in Nehalem.[12]
256-bit/cycle ring bus interconnect between cores, graphics, cache and System Agent Domain
Advanced Vector Extensions (AVX) 256-bit instruction set with wider vectors, new extensible syntax and rich functionality[13]
Up to 8 physical cores, or 16 logical cores through hyper-threading (From 6 core/12 thread)
Integration of the GMCH (integrated graphics and memory controller) and processor into a single die inside the processor package. In contrast, Sandy Bridge's predecessor, Clarkdale, has two separate dies (one for GMCH, one for processor) within the processor package. This tighter integration reduces memory latency even more.
Integrated graphics is now integrated on the same die
I/O
Integrated PCIe Controller
Models and steppings
All Sandy Bridge processors with one, two, or four cores report the same CPUID model 0206A7h[18] and are closely related. The stepping number cannot be seen from the CPUID but only from the PCI configuration space. The later Sandy Bridge-E processors with up to eight cores and no graphics are using CPUIDs 0206D6h and 0206D7h.[19] Ivy Bridge CPUs all have CPUID 0306A9h to date, and are built in four different configurations differing in the number of cores, L3 cache and GPU execution units:
The average performance increase, according to IXBT Labs and Semi Accurate as well as many other benchmarking sites, at clock to clock is 11.3% compared to the Nehalem generation, which includes Bloomfield, Clarkdale, and Lynnfield processors.[20]
Around twice the integrated graphics performance compared to Clarkdale's (12 EUs comparison).
List of Sandy Bridge processors
1Processors featuring Intel's HD 3000 graphics are set in bold. Other processors feature HD 2000 graphics, HD graphics (Pentium and Celeron models) or no graphics core (Graphics Clock rate indicated by N/A).
This list may not contain all the Sandy Bridge processors released by Intel. A more complete listing can be found on Intel's website.
XM – Quad-core extreme mobile (unlocked clock multiplier)
E – Embedded mobile processors
QE – Quad-core
LE – Low power
UE – Ultra low power
Cougar Point chipset flaw
On 31 January 2011, Intel issued a recall on all 67-series motherboards due to a flaw in the Cougar Point Chipset.[37] A hardware problem exists, in which the chipset's SATA II ports may fail over time, causing failure of connection to SATA devices, though data is not at risk.[38] Intel claims that this problem will affect only 5% of users over 3 years; however, heavier I/O workloads can exacerbate the problem. This hardware bug cannot be fixed by BIOS update.
Intel stopped production of flawed B2 stepping chipsets and began producing B3 stepping chipsets with the silicon fix. Shipping of these new chipsets started on 14 February 2011 and Intel estimated full recovery volume in April 2011.[39] Motherboard manufacturers (such as ASUS and Gigabyte Technology) and computer manufacturers (such as Dell and Hewlett-Packard) stopped selling products that involved the flawed chipset and offered support for affected customers. Options ranged from swapping for B3 motherboards to product refunds.[40][41]
Sandy Bridge processor sales were temporarily on hold, as one cannot use the CPU without a motherboard. However, processor release dates were not affected.[42] After two weeks, Intel continued shipping some chipsets, but manufacturers had to agree to a set of terms that will prevent customers from encountering the bug.[43]
Limitations
Overclocking
With Sandy Bridge, Intel has tied the speed of every bus (USB, SATA, PCI, PCIe, CPU cores, Uncore, memory etc.) to a single internal clock generator issuing the basic 100 MHz Base Clock (BClk).[44] With CPUs being multiplier locked, the only way to overclock is to increase the BClk, which can be raised by only 5–7% without other hardware components failing. As a work around, Intel made available K/X-series processors, which feature unlocked multipliers; with a multiplier cap of 57 for Sandy Bridge.[45] For the Sandy Bridge-E platform, there is alternative method known as the BClk ratio overclock.[46]
During IDF (Intel Developer Forum) 2010, Intel demonstrated an unknown Sandy Bridge CPU running stably overclocked at 4.9 GHz on air cooling.[47][48]
Chipset
Non-K edition CPUs can overclock up to four bins from its turbo multiplier. Refer here for chipset support.
Sandy and Ivy Bridge processors with vPro capability have security features that can remotely disable a PC or erase information from hard drives. This can be useful in the case of a lost or stolen PC. The commands can be received through 3G signals, Ethernet, or Internet connections. AES encryption acceleration will be available, which can be useful for video conferencing and VoIP applications.[49][50]
Sandy and Ivy Bridge processors contain a DRM technology that some video streaming web sites rely on to restrict use of their content. Such web sites offer 1080p streaming to users with such CPUs and downgrade the quality for other users.[51]
Intel demonstrated the Haswell architecture in September 2011, released in 2013 as the successor to Sandy Bridge and Ivy Bridge.[53]
Fixes
In 2015, Microsoft released a microcode update for selected Sandy Bridge and Ivy Bridge CPUs for Windows 7 and up that addresses stability issues. However, the update negatively impacts Pentium G3258 and Core i3-4010U CPU models.[54][55][56]
^"Intel® Core™ i7 Processor Family for the LGA-2011 Socket Datasheet, Volume 1"(PDF). Intel. p. 8: "The processor features up to 40 lanes of PCI Express links capable of up to 8.0 GT/s, and 4 lanes of DMI2/PCI Express 2.0 interface with a peak transfer rate of 5.0 GT/s. " p. 10: "Support for PCI Express 2.0 (5.0 GT/s), PCI Express (2.5 GT/s), and capable of up to PCI Express 8.0 GT/s. Up to 40 lanes of PCI Express interconnect for general purpose PCI Express devices capable of up to 8.0 GT/s speeds that are configurable for up to 10 independent ports."
^Angelini, Chris (November 14, 2011). "Intel Core i7-3960X Review: Sandy Bridge-E And X79 Express". Tom's Hardware. p. 2. It turns out that PCI Express 3.0 is, in fact, supported by Sandy Bridge-E (and the preview was updated to confirm 8 GT/s support the day after it went live). But because there weren't (and still aren't) any third-gen devices available yet, validating the feature was problematic. In fact, as you can see in the image below, Intel is still only officially guaranteeing that PCI Express 2.0 works, and probably will continue to do so until we see some hardware with a third-gen interface. Nevertheless, Intel's Core i7 datasheet confirms PCI Express 3.0 compliance, enabling up to 1 GB/s of bandwidth per lane, per direction.
^Shortly before Sandy Bridge-E's release,[25] Intel decided not to claim its PCIe 3.0 support, because the lack of any PCIe 3.0-certified hardware at the time of release would make it difficult to validate compliance. However the ability to operate in the 3.0 mode was preserved, which was confirmed by media and acknowledged by Intel.[26][27][28]
