LGA 2011, also called Socket R, is a CPU socket by Intel. It replaces Intel's LGA 1366 and
LGA 1567 in the performance and high-end desktop and server platforms. The socket has 2011
protruding pins which touch contact points on the underside of the processor.
Socket R uses QPI to connect the CPU to additional CPUs. DMI 2.0 is used to connect the processor
to the PCH. The memory controller and 40 PCIe lanes are integrated on the CPU. On a secondary
processor an extra ×4 PCIe interface replaces the DMI interface. As with its predecessor
LGA 1366 there is no provision for integrated graphics.
The socket was released on 14 November 2011, and supports 4 DDR3 SDRAM memory channels
with 1 unbuffered DIMM per channel, as well as 40× PCIe 2.0 or 3.0 lanes. LGA 2011 also
has to ensure platform scalability beyond eight cores and 20 MB of cache.
LGA 2011 socket is used by Sandy Bridge-E/EP and Ivy Bridge-E/EP processors with the corresponding
X79 and C600-series chipsets. LGA 2011-1, an updated generation of the socket and the
successor of LGA 1567, is used for Ivy Bridge-EX CPUs, which were released in February 2014.
LGA 2011-v3 is another updated generation of the socket, used for Haswell-E CPUs, which
were released in August 2014. Updated socket generations are physically similar to LGA 2011,
but the used electrical signals and ILM keying prevent them from being backward compatible
with older CPUs.
Physical design and socket generations Intel CPU sockets use the so-called Independent
Loading Mechanism retention device that holds the CPU in place while applying an exact amount
of force required for a CPU to be properly seated. As part of their design, ILMs have
differently placed protrusions which are intended to mate with cutouts in CPU packagings. These
protrusions, also known as ILM keying, have the purpose of preventing installation of
incompatible CPUs into otherwise physically compatible sockets, and preventing ILMs to
be mounted with a 180-degree rotation relative to the CPU socket.
Different variants of the LGA 2011 socket and associated CPUs come with different ILM
keying, which makes it possible to install CPUs only into generation-matching sockets.
CPUs that are intended to be mounted into LGA 2011-0, LGA 2011-1 or LGA 2011-v3 sockets
are all mechanically compatible regarding their dimensions and ball pattern pitches,
but the designations of contacts are different between generations of the LGA 2011 socket
and CPUs, thus making them electrically and logically incompatible. Original LGA 2011
socket is used for Sandy Bridge-E/EP and Ivy Bridge-E/EP processors, while LGA 2011-1
is used for Ivy Bridge-EX CPUs, which were released in February 2014. LGA 2011-v3 socket
is used for Haswell-E CPUs, which were released in August 2014.
Chipsets Information for the Intel X79 and C600 series
chipset can be found in the table below. The Romley platform was delayed approximately
one quarter, allegedly due to a SAS controller bug.
The X79 appears to contain the same silicon as the C600 series, with ECS having enabled
the SAS controller for one of their boards, even though SAS is not officially supported
by Intel for X79. Compatible processors
Desktop Information for the desktop LGA 2011 socket
processors can be found in the table below. All models support: MMX, SSE, SSE2, SSE3,
SSSE3, SSE4.1, SSE4.2, AVX, Enhanced Intel SpeedStep Technology, Intel 64, XD bit, TXT,
Intel VT-x, Intel VT-d, Turbo Boost, AES-NI, Smart Cache, Hyper-threading, except the C1
stepping models, which lack VT-d. Sandy Bridge-E, Ivy Bridge-E and Haswell-E
processors are not bundled with standard air-cooled CPU coolers. Intel is offering a standard
CPU cooler, and a liquid-cooled CPU cooler, which are both sold separately.
Sandy Bridge-E and Ivy Bridge-E are compatible with the X79 chipset.
Haswell-E is compatible with the X99 chipset. 1 The X79 chipset allows for increasing the
base clock, Intel calls it CPU Strap, by 1.00×, 1.25×, 1.66× or 2.50×. The CPU frequency
is derived by the BCLK times the CPU multiplier. Server
Information for the server LGA 2011 socket processors can be found in the table below.
All models support: MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, Enhanced Intel
SpeedStep Technology, Intel 64, XD bit, TXT, Intel VT-x, Intel VT-d, AES-NI, Smart Cache.
Not all support Hyper-threading and Turbo Boost.
Independent Loading Mechanism is available in two variants, square and narrow.
References