Vol 1

Technologies
28 Intel® Xeon® Product 2800/4800/8800 v2 Product Family
Datasheet Volume One, February 2014
Note: Intel Turbo Boost Technology is only active if the operating system is requesting the P0
state. For more information on P-states and C-states refer to Chapter 3, “Power
Management.”
2.5 Enhanced Intel SpeedStep® Technology
The processor supports Enhanced Intel SpeedStep Technology as an advanced means
of enabling very high performance while also meeting the power-conservation needs of
the platform.
Enhanced Intel SpeedStep Technology builds upon that architecture using design
strategies that include the following:
• Separation between Voltage and Frequency Changes. By stepping voltage up
and down in small increments separately from frequency changes, the processor is
able to reduce periods of system unavailability (which occur during frequency
change). Thus, the system is able to transition between voltage and frequency
states more often, providing improved power/performance balance.
• Clock Partitioning and Recovery. The bus clock continues running during state
transition, even when the core clock and Phase-Locked Loop are stopped, which
allows logic to remain active. The core clock is also able to restart more quickly
under Enhanced Intel SpeedStep Technology.
For additional information on Enhanced Intel SpeedStep Technology see Section 3.2.1.
2.6 Intel® Advanced Vector Extensions (Intel® AVX)
Intel® Advanced Vector Extensions (Intel® AVX) is a new 256-bit vector SIMD
extension of Intel Architecture. Intel AVX accelerates the trend of parallel computation
in general purpose applications like image, video, and audio processing, engineering
applications such as 3D modeling and analysis, scientific simulation, and financial
analysts.
Intel AVX is a comprehensive ISA extension of the Intel 64 Architecture. The main
elements of Intel AVX are:
• Support for wider vector data (up to 256-bit) for floating-point computation.
• Efficient instruction encoding scheme that supports 3 operand syntax and
headroom for future extensions.
• Flexibility in programming environment, ranging from branch handling to relaxed
memory alignment requirements.
• New data manipulation and arithmetic compute primitives, including broadcast,
permute, fused-multiply-add, and so forth.
The key advantages of Intel AVX are:
• Performance - Intel AVX can accelerate application performance via data
parallelism and scalable hardware infrastructure across existing and new
application domains:
— 256-bit vector data sets can be processed up to twice the throughput of 128-bit
data sets.
— Application performance can scale up with number of hardware threads and
number of cores.
— Application domain can scale out with advanced platform interconnect fabrics,
such as Intel QPI.