Pentium 4 Extreme Edition was released on november 2003 and was the first desktop CPU to carry an integrated L3 memory cache. This processor has 2 MB of L3 memory cache accessed under the CPU internal clock. The first Pentium 4 Extreme Edition Models were based on the Gallatin core, which had 512 KB of L2 memory cache and 2 MB of L3 memory cache, ran externally at 800 MHz or 1,066 MHz (200 MHz or 266 MHz transferring four data per clock cycle, respectively), SSE2 instruction set, 64-bit extensions, HyperThreading technology, 0.13 µm manufacturing process and 178 million transistors. Pentium 4 Extreme Edition models available today are based on Prescott 2M core, which is manufactured using 90 nm process. Below you can compare Prescott core (used by regular Pentium 4 processors) with Prescott 2M core (used by Pentium 4 Extreme Edition processors).

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Figure 4: Prescott core.

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Figure 5: Prescott 2M core.

While Prescott core has 125 million transistors, Prescott 2M core has 169 million. This difference goes to the 2 MB L2 memory cache that exists on Prescott 2M.

So far Intel has released only one Pentium 4 Extreme Edition based on Prescott 2M core. This processor has 2MB L2 memory cache, SSE3 instruction set, HyperThreading technology and 64-bit extensions.

Below we list all Pentium 4 Extreme Edition models launched so far.

Model	Internal Clock	External Clock	TDP	Max. Temp. (º C)	L2 Cache	L3 Cache	Socket	Tecnology	Hyper-Threading
SL7Z4	3.73 GHz	1066 MHz	115 W	72.8	2 MB	-	775	0.09 µm	Yes
SL7RT	3.46 GHz	1066 MHz	110.7 W	66	2 MB	-	775	0.13 µm	yes
SL7NF	3.46 GHz	1066 MHz	110.7 W	66	512 KB	2 MB	775	0.13 µm	yes
SL7RR	3.40 GHz	800 MHz	109.6 W	66	512 KB	2 MB	775	0.13 µm	yes
SL7GD	3.40 GHz	800 MHz	109.6 W	66	512 KB	2 MB	775	0.13 µm	yes
SL7CH	3.40 GHz	800 MHz	102.9 W	67	512 KB	2 MB	478	0.13 µm	yes
SL7AA	3.20 GHz	800 MHz	92.1 W	64	512 KB	2 MB	478	0.13 µm	yes