The Intel Core Duo processor is Intel's first mobile dual core processor for notebooks and a key component of the Intel Centrino processor technology. It belongs to the Core processor family, is based on the Pentium M architecture (two improved Pentium M cores) and the direct predecessor of the Intel Core 2 Duo notebook processors, which were introduced in July 2006.

The Intel Core Duo processor integrates two 32-Bite cores (based on the Pentium M), which are optimised for mobile operation in a single processor. Therewith, it is possible to run threads and application in separate cores with separate CPU resources in parallel and, so, the performance can increase depending on the other hardware components if this feature is supported by the operating system and the software.

Later on the design of the Core Duo was reused for the Pentium Dual-Core (an inexpensive alternative to the Core 2 Duo and a direct competitor of the Turion (64) X2 processors).

• Two 32 Bit Cores with shared L2 cache
• Intel Smart Cache – 2MB L2 cache with enhanced Transfer Cache Architecture
• Intel Digital Media Boost
• Intel Dynamic Power Coordination with Dynamic Bus Parking
• Enhanced Intel Deeper Sleep with Intel Smart Cache Sizing
• Intel Advanced Thermal Manager
• Power-Optimized 667 MHz System Bus (all but Uxxxx processors)
• Enhanced Intel SpeedStep Technology Support
• 65nm lithography

All Core Duo processors are produced in 65 nm technology and have 2 MB level 2 cache. Depending on the model the front-side-bus works either on 667 MHz or on 533 MHz (ultra-low-voltage models). The ultra-low-voltage models require 9.0 Watt, the low-voltage models 15 Watt, all other have an energy demand of 13 Watt. The clock rates of this processor series ranges from 1.06 GHz up to 2.33 GHz. Furthermore, all models implement Intel's Enhanced Speedstep technology, and Execute-Disable-Bit and some of the Intel's Virtualisation technology. The Intel Core Duo is alike the Intel Core Solo and the Intel Xeon dual core processor LV based on the enhanced Pentium M processor microarchitecture.

Enhanced Pentium M Architecture
The Intel Core processor is based on the Pentium M architecture. The Pentium M  brings compared to the former mobile IA-32 processors an improved micro-architecture, a lower energy demand and a good performance. The aim was a longer battery life and being ready for new fields of operation by, e.g., enhanced mobility, a very thin shape, integrated wireless LAN. Thereby the following enhancements were implemented:

• Support of Intel architectures with Dynamic Execution
• 32-KByte Instruction-Cache and 32-KByte Write-Back-Data-Cache on-chip
• Up to 2 MByte Second-Level-Cache wich enhanced Transfer-Cache-Architecture
• Enhanced Branch-Prediction and Data-Prefetch-Logic
• Support for MMX-Technology, Streaming-SIMD instructions, and the SSE2 instruction set
• A 400 or 533 MHz Source-Synchronous system bus
• Enhanced Power-Management by Enhanced Intel SpeedStep technology

Dual Core Architecture
The Pentium M architecture was further enhanced for the Core Duo (and the Core Solo). The enhancements include:

• Intel Smart Cache, which improves the data sharing of the two processor cores.
• Enhanced decoding and SIMD execution
• Intel Dynamic Power Coordination and Enhanced Intel Deeper Sleep for reducing the energy demand
• Intel Advanced-Thermal-Manager, which offers digital interfaces to the temperature sensor.
• Support of the performance-oriented 667 MHz bus
• SSE3 enhancement of the instruction set

Dualcore Technik
Two processor cores work inside a single processor component at the same clock frequency and share the L2 cache and the front side bus (FSB).

Execute Disable Bit
prohibits security problems caused by buffer overflows if it is activated and supported by the operating system.

Dynamic Execution
includes deep-branch prediction, micro-data flow analysis, out-of-order execution, superior branch prediction, and speculative execution

Smart-Cache
2 MB Level 2 Cache with enhanced cache architecture make the cache more efficient (compared to the Pentium M architecture).

Advanced Thermal Manager
The Thermal Management system, which was enhanced compared to the Pentium M architecture, improves the control and, therefore, allows quieter, cooler, and slimmer notebooks.

Virtualization Technology (VT)
The Intel VT offers hardware support of virtual systems on a single computer (i.e., using more operating systems in parallel and isolated from each other, e.g., Xen or VMWare).

Digital Media Boost
The Digital-Media-Boost is an enhancement of the micro-architecture, which optimises instructions and improves the performance for the purpose of accelerating calculation intensive tasks like audio, and video processing, picture editing, 3D graphics and scientific calculations.

Am 9. Mai 2007 wurde im Zuge der 4. Centrino Generation namens Santa Rosa auch der Core 2 Duo Prozessor erneuert. Der Prozessor basiert immer noch auf dem Merom Kern, wurde jedoch um einige Stromspar- und Optimierungsfunktionen erweitert. Ausserdem braucht er nun den neuen Socket P mit 478 Pins, der jedoch nicht mehr Pin-kompatibel mit dem Socket M der älteren Core 2 Duo ist.

Im Unterschied zu den Vorgänger Core 2 Duo Prozessoren arbeiten die neuen CPUs nun mit FSB 800 (200 MHz Quad-pumped) anstatt FSB 667 (133 MHz Quad-pumped).

Dieser unterstützt nun "Dynamic Front Side Bus Switching", wobei bei geringer Prozessorlast der FSB von 200 MHz auf bis zu 100 MHz (FSB 400) abgesenkt werden kann um Energie zu sparen. Diese Absenkung betrifft jedoch nur Chipsatz und Prozessor und wird daher "virtuell" genannt. Der Core 2 Duo kann sich dank Speedstep auf minimal 1.2 GHz runtertakten. Dank dem niedrigeren (virtuellen) FSB kann sich der "Santa Rosa" Core 2 Duo auf 800 MHz heruntertakten um noch mehr Strom zu sparen.

Ein weiteres neues Feature ist das dynamische Übertakten eines Kerns namens "Dynamic Acceleration". Wenn nur ein Kern des Prozessors gefordert wird, dann kann sich der eine Kern dynamisch übertakten, während der zweite Kern in den stromsparenden C3-Modus verweilt. Dadurch kann der übertaktete Kern mit der Taktrate des nächshöheren Modells arbeiten (z.B. 2.2 statt 2.0 GHz beim T7300). Dadurch bleibt die TDP (Thermal Design Power) gleich und erfordert keine angepassten Kühllösungen.

Wenn der Prozessor gerade keine Aufgabe zum Abarbeiten hat, begibt er sich in die unterschiedliche Sparzustände (C1 bis C4/DC4). Bei Santa Rosa sorgt der neue Chipsatz dafür, das der Prozessor so lange wie mögliche im Sparzustand verbleibt (z.B. fängt er Speicheranfragen ab).

Processor numbers for the Intel Core CPU are categorized in 4-digit numerical sequences with an alphabetical prefix. All processors with leading 'T' have standard energy demand. Except of these there are also Lxxxx (low-voltage) and Uxxx (ultra-low voltage) processors available.

The following number is based on a variety of

• Cache
• Front side bus
• Clock speed
• Power
• New Instructions
• Other Intel technologies.

Thereby a higher number hints on more features, but this can also mean that a  processor features more of an aspect, but less of another.

A detailed list of all models is available in our overview of mobile processors.

A categorization according to performance of all mobile processors is available in our benchmark list of mobile processors.