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Intel Pentium 4 Hyper Threading Processors
http://www.hardwaretipsandtricks.com/articles/156/1/Intel-Pentium-4-Hyper-Threading-Processors/Page1.html
By Super Admin
Published on 11/26/2006
 
Hyper-threading, officially called Hyper-Threading Technology (HTT), is Intel's trademark for their implementation of the simultaneous multithreading technology on the Pentium 4 microarchitecture.

Intel Pentium 4 Hyper Threading Processors
Model Number Frequency L2-Cache Front Side Bus Multiplier Voltage TDP Socket Release Date Part Number(s)
Pentium 4 HT 2.4C 2400 MHz 512 KiB 800 MT/s 12x 1.475/1.525 V 66.2 W Socket 478 May 21, 2003 RK80532PG056512
Pentium 4 HT 2.6C 2600 MHz 512 KiB 800 MT/s 13x 1.475/1.525 V 69 W Socket 478 May 21, 2003 RK80532PG064512
Pentium 4 HT 2.8C 2800 MHz 512 KiB 800 MT/s 14x 1.475/1.525 V 69.7 W Socket 478 May 21, 2003 RK80532PG072512
Pentium 4 HT 3.0 3000 MHz 512 KiB 800 MT/s 15x 1.475/1.55 V 81.9 W Socket 478 April 14, 2003 RK80532PG080512
Pentium 4 HT 3.06 3066 MHz 512 KiB 533 MT/s 23x 1.475/1.55 V 81.8 W Socket 478 November 14, 2002 RK80532PE083512
Pentium 4 HT 3.2 3200 MHz 512 KiB 800 MT/s 16x 1.475/1.55 V 82 W Socket 478 June 23, 2003 RK80532PG088512
Pentium 4 HT 3.4 3400 MHz 512 KiB 800 MT/s 17x 1.475/1.55 V 89 W Socket 478 February 1, 2004 RK80532PG096512

 

Model Number Frequency L2-Cache Front Side Bus Multiplier Voltage TDP Socket Release Date Part Number(s)
Pentium 4 HT 2.8E 2800 MHz 1024 KiB 800 MT/s 14x 1.25/1.4 V 89 W Socket 478 February 1, 2004 RK80546PG0721M
Pentium 4 HT 3.0E 3000 MHz 1024 KiB 800 MT/s 15x 1.25/1.4 V 89 W Socket 478 February 1, 2004 RK80546PG0801M
Pentium 4 HT 3.2E 3200 MHz 1024 KiB 800 MT/s 16x 1.25/1.4 V 89/103 W Socket 478 February 1, 2004 RK80546PG0881M
Pentium 4 HT 3.2F 3200 MHz 1024 KiB 800 MT/s 16x 1.25/1.4 V 84 W LGA 775 August 2004  
Pentium 4 HT 3.4E 3400 MHz 1024 KiB 800 MT/s 17x 1.25/1.4 V 89/103 W Socket 478 February 1, 2004 RK80546PG0961M
Pentium 4 HT 3.4F 3400 MHz 1024 KiB 800 MT/s 17x 1.25/1.4 V 115 W LGA 775 August 2004  
Pentium 4 HT 3.6F 3600 MHz 1024 KiB 800 MT/s 18x 1.25/1.4 V 115 W LGA 775 August 4, 2004  
Pentium 4 HT 3.8F 3800 MHz 1024 KiB 800 MT/s 19x 1.25/1.4 V 115 W LGA 775 November 2004  
Pentium 4 HT 517 2933 MHz 1024 KiB 533 MT/s 22x 1.25/1.4 V 84 W LGA 775 September 2005 HH80547PE0771MM
Pentium 4 HT 520 2800 MHz 1024 KiB 800 MT/s 14x 1.25/1.4 V 84 W LGA 775 June 2004 JM80547PG0721M
Pentium 4 HT 520J 2800 MHz 1024 KiB 800 MT/s 14x 1.25/1.4 V 84 W LGA 775 October 2004 JM80547PG0721M
Pentium 4 HT 521 2800 MHz 1024 KiB 800 MT/s 14x 1.25/1.4 V 84 W LGA 775 June 12, 2005 JM80547PG0721MM
HH80547PG0721MM
Pentium 4 HT 524 3066 MHz 1024 KiB 533 MT/s 23x     LGA 775   HH80547PE0831MM
Pentium 4 HT 530 3000 MHz 1024 KiB 800 MT/s 15x 1.25/1.4 V 84 W LGA 775 June 2004 JM80547PG0801M
Pentium 4 HT 530J 3000 MHz 1024 KiB 800 MT/s 15x 1.25/1.4 V 84 W LGA 775 October 2004 JM80547PG0801M
Pentium 4 HT 531 3000 MHz 1024 KiB 800 MT/s 15x 1.25/1.4 V 84 W LGA 775 June 12, 2005 JM80547PG0801M
HH80547PG0801M
Pentium 4 HT 540 3200 MHz 1024 KiB 800 MT/s 16x 1.25/1.4 V 84 W LGA 775 June 21, 2004 JM80547PG0881M
Pentium 4 HT 540J 3200 MHz 1024 KiB 800 MT/s 16x 1.25/1.4 V 84 W LGA 775 October 2004 JM80547PG0881M
Pentium 4 HT 541 3200 MHz 1024 KiB 800 MT/s 16x 1.25/1.4 V 84 W LGA 775 June 12, 2005 JM80547PG0881MM
HH80547PG0881MM
Pentium 4 HT 550 3400 MHz 1024 KiB 800 MT/s 17x 1.25/1.4 V 84 W LGA 775 June 21, 2004 JM80547PG0961M
Pentium 4 HT 550J 3400 MHz 1024 KiB 800 MT/s 17x 1.25/1.4 V 84 W LGA 775 October 2004 JM80547PG0961M
Pentium 4 HT 551 3400 MHz 1024 KiB 800 MT/s 17x 1.25/1.4 V 84 W LGA 775 June 12, 2005 JM80547PG0961MM
HH80547PG0961MM
Pentium 4 HT 560 3600 MHz 1024 KiB 800 MT/s 18x 1.25/1.4 V 115 W LGA 775 June 21, 2004 JM80547PG1041M
Pentium 4 HT 560J 3600 MHz 1024 KiB 800 MT/s 18x 1.25/1.4 V 115 W LGA 775 October 2004 JM80547PG1041M
Pentium 4 HT 561 3600 MHz 1024 KiB 800 MT/s 18x 1.25/1.4 V 115 W LGA 775 June 12, 2005 JM80547PG1041MM
Pentium 4 HT 570J 3800 MHz 1024 KiB 800 MT/s 19x 1.25/1.4 V 115 W LGA 775 November 12, 2004 JM80547PG1121M
Pentium 4 HT 571 3800 MHz 1024 KiB 800 MT/s 19x 1.25/1.4 V 115 W LGA 775 June 12, 2005 JM80547PG1121MM

 

Model Number Frequency L2-Cache Front Side Bus Multiplier Voltage TDP Socket Release Date Part Number(s)
Pentium 4 HT 620 2800 MHz 2048 KiB 800 MT/s 14x 1.2/1.4 V 84 W LGA 775   JM80547PH1072MM
Pentium 4 HT 630 3000 MHz 2048 KiB 800 MT/s 15x 1.2/1.4 V 84 W LGA 775 February 20, 2005 JM80547PG0802M
Pentium 4 HT 640 3200 MHz 2048 KiB 800 MT/s 16x 1.2/1.4 V 84 W LGA 775 February 20, 2005 JM80547PG0882M
Pentium 4 HT 650 3400 MHz 2048 KiB 800 MT/s 17x 1.2/1.4 V 84 W LGA 775 February 20, 2005 JM80547PG0962M
Pentium 4 HT 660 3600 MHz 2048 KiB 800 MT/s 18x 1.2/1.4 V 115 W LGA 775 February 20, 2005 JM80547PG1042M
Pentium 4 HT 662 3600 MHz 2048 KiB 800 MT/s 18x 1.2/1.4 V 115 W LGA 775 November 14, 2005 HH80547PG1042MH
Pentium 4 HT 670 3800 MHz 2048 KiB 800 MT/s 19x 1.2/1.4 V 115 W LGA 775 May 26, 2005 JM80547PG1122M
Pentium 4 HT 672 3800 MHz 2048 KiB 800 MT/s 19x 1.2/1.4 V 115 W LGA 775 November 14, 2005 HH80547PG1122MH

 

Model Number Frequency L2-Cache Front Side Bus Multiplier Voltage TDP Socket Release Date Part Number(s)
Pentium 4 HT 631 3000 MHz 2048 KiB 800 MT/s 15x 1.2/1.4 V 86 W LGA 775 January 16, 2006 HH80552PG0802M
Pentium 4 HT 641 3200 MHz 2048 KiB 800 MT/s 16x 1.2/1.4 V 86 W LGA 775 January 16, 2006 HH80552PG0882M
Pentium 4 HT 651 3400 MHz 2048 KiB 800 MT/s 17x 1.2/1.4 V 86 W LGA 775 January 16, 2006 HH80552PG0962M
Pentium 4 HT 661 3600 MHz 2048 KiB 800 MT/s 18x 1.2/1.4 V 86 W LGA 775 January 16, 2006 HH80552PG1042M


Hyper-threading, officially called Hyper-Threading Technology (HTT), is Intel's trademark for their implementation of the simultaneous multithreading technology on the Pentium 4 microarchitecture. It is a more advanced form of Super-threading that debuted on the Intel Xeon processors and was later added to Pentium 4 processors. The technology improves processor performance under certain workloads by providing useful work for execution units that would otherwise be idle, for example during a cache miss. A Pentium 4 with Hyper-Threading enabled is treated by the operating system as two processors instead of one.

The advantages of Hyper-Threading are listed as: improved support for multi-threaded code, allowing multiple threads to run simultaneously, improved reaction and response time, and increased number of users a server can support.

According to Intel, the first implementation only used an additional 5% of the die area over the "normal" processor, yet yielded performance improvements of 15–30%.

Intel claims up to a 30% speed improvement compared against an otherwise identical, non-SMT Pentium 4. The performance improvement seen is very application-dependent, however, and some programs actually slow down slightly when Hyper Threading Technology is turned on. This is due to the replay system of the Pentium 4 tying up valuable execution resources, thereby starving the other thread. However, any performance degradation is unique to the Pentium 4 (due to various architectural nuances), and is not characteristic of simultaneous multithreading in general.