CPU Specifications - Specifications
Core development name	This is the name used by the vendor to differentiate the core's development from other projects.  Not all CPUs have a unique codename and are simply known by their model title.
Core construction size	This value refers to the size of the general components, such as a transistor, inside the chip core.  Other components, such as interconnects, may be larger or even smaller than this.  The units of nm are nanometres or 0.000000001 metres.
Core transistor count	This value, given by the manufacturer, refers to the approximate number of transistors within the processing core.  Vendors often count up the transistors via different methods, so directly comparing one product to another is not always possible.
Number of processor cores	The number of discrete, fully duplicated processors within the CPU module; each core may be on separate die or together on a single piece.
Core registers - ALU	A register is a very small piece of memory used to store the individual digital figures used by the processor in calculations.  The Arithmetic Logic Units (ALUs) work on integer (whole) numbers and this value refers to the size of the "general" registers (in bits) in the ALUs.
Core registers - FPU	A register is a very small piece of memory used to store the individual digital figures used by the processor in calculations.  The Floating Point Units (ALUs) work on fractional numbers and this value refers to the size of the registers (in bits) in the FPUs.  The ( Ext) number refers to the largest registers used by the extensions (MMX, SSE, etc).
Connection type	This is the type of socket, slot or pin layout that is used to connect the CPU module to the motherboard.
Model name / Core speed	Older CPUs are simply named by their primary internal clock speed (either in MHz or GHz - one Hz is one cycle per second).  Newer CPUs are typically given a name that is used to approximate their performance arelative to other models - in such cases, the "performance rating" name is given first, followed by the core speed.
FSB / HyperTransport CLK speed	CPUs communicate to other components in the motherboard via a Front Side Bus (FSB) or a HyperTransport link.  In both cases, there is a central timing voltage link (CLK) that is used to synchronise and regulate the clock speeds of other components;  the internal clock speed of a CPU is of a fixed multiple of the CLK speed.  The value is rated in MHz.
FSB / HyperTransport data transfer rate	This value refers to the rate at which units of data are transferred across the FSB or HyperTransport link.  The value is rated in MHz, which one Hz equates to one unit of data transferred per second.
FSB / HyperTransport total bus width	The FSB of a CPU contains voltage lines which are used to transfer data (a role also replicated by a HyperTransport link).  This value refers to the total width of all the transfer links in a single cycle: multiple links or bidirectional links accumulate.  The value is given in bits.
FSB / HyperTransport maximum bandwidth	This is the theoretically maximum amount of data that can be transferred via the FSB or HyperTransport link in one second; the value is in MB/sec or GB/sec.
Integrated memory controller width	If the CPU contains an integrated memory controller (instead of using that found in the Northbridge chip on the motherboard), then this value refers to the accumulated total width of all the controllers and is given in bits.
Integrated memory controller max DRAM CLK speed	DRAM modules are timed by a central CLK voltage line (similar to that found in the FSB or HyperTransport link).  This value refers to the maximum speed the controller supports, in MHz.
Integrated memory controller type	Integrated memory controllers can only support one type of DRAM, due to the different signalling and trace layout required by each type.  DDR SDRAM, DDR2 SDRAM or DDR3 SDRAM are typical.
Integrated memory controller type maximum bandwidth	This is the theoretically maximum amount of data that can be transferred via the integrated memory controller in one second; the values in MB/sec or GB/sec.
L1 / L2 / L3 cache amount	Cache is used to store small pieces of data or instructions that can beaccessed by the CPU quicker than via the system memory.  L1 cache is the first to be checked, as it is the smallest and has the shortest levels of latency.  Higher levels of cache are usually much largerbut are slower to be read and written to.  The amount is given in kibibytes (KiB) or mebibytes (MiB).
L1 / L2 / L3 cache location	Cache is most useful if it is on-die (i.e. integrated with the CPU core itself) but may also be found externally as SRAM chips on the CPU module's PCB or motherboard.
L1 instruction / trace cache size	This value refers to the amount of L1 cache used to store instructions or decoded micro operations (trace cache).
L1 data cache size	This value refers to the amount of L1 cache used to store data.
L2 / L3 cache bus width	Since L2 and higher levels of cache are much larger than L1 cache, the communication bus to that cache is often narrower.  This value gives the size of the bus width to that cache.
MMX extension support	Indicates whether the CPU supports MMX instruction extensions or not.
3DNow! extension support	Indicates whether the CPU supports 3DNow! instruction extensions or not.  At present, no Intel CPU supports these extensions.
SSE extension support	Indicates whether the CPU supports SSE instruction extensions or not.
Extended 3DNow! extension support	Indicates whether the CPU supports Enhanced 3DNow! instruction extensions or not.  At present, no Intel CPU supports these extensions.
3DNow! Professional support	Indicates whether the CPU support 3DNow! Professional instruction extensions or not.  At present, no Intel CPU supports all of the instructions in this extension set.
SSE2 extension support	Indicates whether the CPU supports SSE2 instruction extensions or not.
SSE3 extension support	Indicates whether the CPU supports SSE3 instruction extensions or not.  AMD and Intel chips do not support the exact same amount of instructions offered by SSE3.
SSSE3 extension support	Indicates whether the CPU supports SSSE3 instruction extensions or not.  At present, no AMD CPU supports these extensions.
SSE4 extension support	Indicates whether the CPU supports SSE4 instruction extensions or not.  SSE4(a) is AMD-only, whereas SSE4.1 and 4.2 are Intel-only.
Intel 64 feature support	Indicates whether the CPU supports Intel's set of 64 bit x86 instructions or not.
AMD 64 feature support	Indicates whether the CPU supports AMD's set of 64 bit x86 instructions or not.
HyperThreading feature support	Indicates whether the CPU supports Intel's proprietary HyperThreading technology or not.
NX Bit feature support	Indicates whether the CPU supports No Execute technology or not.
Virtualization Technology feature support	Indicates whether the CPU offers technology to enable x86 virtualization or not.
© AMD & Intel CPU Specifications Terminology - N D Evanson 2008