Merom (microprocessor)
Introduction '''''Merom''''' is the code name for various mobile Intel processors that are sold as Core 2 Duo, Core 2 Solo, Pentium Dual-Core and Celeron. It was the first mobile processor to be based on the Core microarchitecture, replacing the Enhanced Pentium M-based Yonah processor. Merom has the product code 80537, which is shared with ''Merom-2M'' and ''Merom-L'' that are very similar but have a smaller L2 cache. Merom-L has only one processor core and a different CPUID model. The desktop version of Merom is Conroe and the dual-socket server version is Woodcrest. Merom was manufactured in a 65 nanometer process, and was succeeded by Penryn, a 45 nm version of the Merom architecture. Together, Penryn and Merom represented the first 'tick-tock' in Intel's Tick-Tock manufacturing paradigm, in which Penryn was the 'tick' (new process) to Merom's 'tock' (new architecture).
Variants  Processor  Brand name  Model (list)  Cores  L2 Cache  Socket  TDP Merom-L Mobile Core 2 Solo U2xxx  1  2 MiB  BGA479  5.5 W Merom-2MMobile Core 2 Duo U7xxx 2  2 MiB BGA479  10 W Merom L7xxx   4 MiB  17 W MeromMerom-2M T5xxxT7xxx  2-4 MiB  Socket MSocket PBGA479  35 W Merom Mobile Core 2 Extreme X7xxx  2  4 MiB  Socket P  44 W MeromCeleron M (Socket M) and Celeron (Socket P) 5x0  1 1024 KiB Socket MSocket P  30 W Merom-L 5x0  27 W Merom-2M 5x5  1024 KiB  Socket P  31 W Merom-L 5x3  512-1024 KiB  BGA479  5.5-10 W Merom-2M Celeron Dual-Core T1xxx  2  512-1024 KiB  Socket P  35 W Merom-2M Pentium Dual-Core T2xxxT3xxx  2  1 MiB  Socket P  35 W===Merom==='''Merom''', the first mobile version of the Core 2, was officially released on July 27, 2006, but quietly began shipping to PC manufacturers in mid-July, alongside Conroe. Merom became Intel's premier line of mobile processors, with mostly the same features as Conroe, but with a greater emphasis on low power consumption to enhance notebook battery life. Merom-based Core 2 Duo provides a slight performance increase associated with 3D rendering and media-encoding tasks, yet maintains the same battery life as the Yonah-based Core Duo. Merom is the first Intel mobile processor to feature Intel 64 architecture.The first version of Merom is "drop-in" compatible with Napa platform for Core Duo, requiring at most a motherboard BIOS update. It has a similar thermal envelope of 34 W and the same 667 MT/s FSB rate. The Merom die features 4 MB L2 cache, half of which is deactivated in the T5xx0 CPUs. A native 2 MB L2 version of the Merom core, called Merom-2M, was rolled out in early 2007 as a counterpart to ''Allendale''. The Merom-2M core uses the steppings L2 and M0 and the ultra-low-voltage versions of the Core 2 Duo use this core.A second wave of Merom processors featuring an 800 MT/s FSB and using the new Socket P was launched on May 9, 2007.These chips are part of Santa Rosa platform. Low voltage versions were also released on May 9, 2007. ''Merom'' (מרום) is the Hebrew word for a higher plane of existence or a level of heaven; ''BaMerom'' (במרום) means "in the heavens". The name was chosen by the Intel team in Haifa, Israel, who designed this processor.====Merom XE====The Core 2 Extreme Mobile processor, based on the '''Merom XE''' core, is a mobile CPU designed for laptops. It was released in two models, the X7900 and the X7800.These feature an 800 MT/s FSB. The X7800, introduced on July 16, 2007, is clocked at 2.6 GHz and costs around $851 for OEMs. The processor features a 44 W TDP and requires the new Intel Centrino (Santa Rosa) platform. The X7900, introduced on August 22, 2007, is clocked at 2.8 GHz.The X7900 processor was used in the top-end iMacs released on August 7, 2007.===Merom-2M===The mobile version of the Allendale desktop processor is often called Merom-2M to identify the smaller L2 cache. Some T5xxx and T7xxx processors have come out with both Merom and Merom-2M dies, which can only be distinguished through their stepping number.=== Merom-L ===The Merom-L processor is based on the same model as Conroe-L but is used in mobile Socket M and Socket P systems as Celeron 5xx and Core 2 Solo U2xxx, some of which also use regular Merom and Merom-2M chips with one core disabled in contrast to the real Merom-L that only has 1 MB L2 cache and a single core. The CPUID is family 6 model 23 (10661h), which is between Merom and Penryn.The first Core 2 Solo processors were launched in Q3 2007 and consisted of the U2100 and U2200, which run at 1.06 and 1.2 GHz, respectively. They both feature a 533 MT/s FSB and are part of Intel's ULV family, running at only 5 W. Like the rest of the Core 2 family, they are 64-bit compatible. They were released with compatibility for the Napa platform rather than the newer Santa Rosa platform due to power consumption concerns.
Fixes Microsoft has released a microcode update (KB2493989) for Windows 7 that addresses several stability issues on selected "Penryn" and "Merom" CPUs.
See also * Yonah (microprocessor)* Conroe (microprocessor)* Penryn (microprocessor)* Celeron* Pentium Dual-Core* Intel Core 2* List of Macintosh models grouped by CPU type
References
External links *  List of Intel processors codenamed Merom