LGA 771, also known as Socket J, is a CPU interface introduced by Intel in 2006. It is used in Intel Core microarchitecture and NetBurst microarchitecture (Dempsey) based DP-capable server processors, the Dual-Core Xeon is codenamed Dempsey, Woodcrest, and Wolfdale and the Quad-Core processors Clovertown, Harpertown, and Yorkfield-CL. It is also used for the Core 2 Extreme QX9775, and blade servers designated under Conroe-CL, and was discontinued around the same time the last processors supporting this socket ceased production in 2011, in favor of its successor, LGA 1366, for the Nehalem-based Xeon processors.
Technical specifications
As its name implies, it is a land grid array with 771 contacts. The socket has 771 protruding spring-loaded pins which touch the lands on the underside of the microprocessor.
The "J" in "Socket J" refers to the now-canceled processor codenamed "Jayhawk", which was expected to debut alongside this interface. It is intended as a successor to Socket 604 and takes much of its design from LGA 775 and is almost pin compatible with LGA 775.
Compared to LGA 775 CPUs, LGA 771 CPUs are rotated 90 degrees and have two pins swapped. Small adapters developed by Chinese computer DIY enthusiasts are available to allow LGA 771 CPUs to be installed in LGA 775 motherboards, if the BIOS microcode supports them (but it is also possible to add supporting microcode manually). This also allows for overclocking of Xeon (LGA 771) processors when used in the correct (LGA 775) motherboards. Some overclockers have managed quite substantial overclocks such as 4.023GHz on a Xeon X5492 for a total overclock of just over 18%.
Single core processors NameCoresFrequencyL2 CacheTDP FSBRelease datePriceXeon 3000 seriesXeon L3014 12.40 GHz3 MB30W1066Q1 2008OEMCeleron 400 seriesCeleron 44511.87 GHz512 KB65W1066OEM
Dual core processors
Hyper-threading supported only on 50xx series processors(codenamed Dempsey) NameCoresFrequencyL2 CacheTDPFSBRelease datePriceXeon 5000 seriesXeon 503022.66 GHz2*2 MB95W667Xeon 50402.83 GHzXeon 50503.00 GHzXeon 50603.20 GHz130W1066Xeon 50633.20 GHz95WXeon 50703.46 GHz130WXeon 50803.73 GHz130WXeon 3100 seriesXeon E311323.00 GHz6 MB65W1333Q3 2008OEMXeon 5100 seriesXeon 511021.60 GHz4 MB65W1066Xeon 51201.86 GHz1066Xeon 51302.00 GHz1333Q2 2006Xeon 51402.33 GHzXeon LV 51482.33 GHz40WXeon 51502.66 GHz65WXeon 51603.00 GHz80WXeon 5200 seriesXeon E520521.86 GHz6 MB65W1066Xeon E52202.33 GHz1333Xeon L521521.86 GHz6 MB20W1066Xeon L52403.00 GHz40W1333Xeon X526023.33 GHz6 MB80W1333Q4 2007Xeon X52703.50 GHz1333Q3 2008Xeon X52723.40 GHz1600Q4 2007
Quad core processors NameCoresFrequencyL2 CacheTDPFSBRelease datePriceXeon 3300 SeriesXeon X332342.50 GHz6 MB80W1333Q1 2008OEMXeon X33532.67 GHz12 MBXeon X33632.83 GHzXeon 5300 seriesXeon E531041.60 GHz8 MB80W1066Q4 2006Xeon E53201.86 GHzXeon E53352.00 GHz1333Q1 2007Xeon E53452.33 GHzXeon L531041.60 GHz8 MB50W1066Q1 2007Xeon L53181.60 GHz40WXeon L53201.86 GHz50WXeon L53352.00 GHz50W1333Q3 2007Xeon X535542.66 GHz8 MB120W1333Q4 2006Xeon X53653.00 GHz150WQ3 2007Xeon 5400 seriesXeon E540542.00 GHz12 MB80W1333Q4 2007Xeon E54102.33 GHzXeon E54202.50 GHzXeon E54302.66 GHzXeon E54402.83 GHzQ1 2008Xeon E54503.00 GHzQ4 2007Xeon E54622.80 GHz1600Xeon E54723.00 GHz1600Xeon L540842.13 GHz12 MB40W1066Q1 2008Xeon L54102.33 GHz50W1333Xeon L54202.50 GHzXeon L54302.66 GHzQ3 2008Xeon X545043.00 GHz12 MB120W1333Q4 2007Xeon X54603.16 GHzXeon X54703.33 GHzQ3 2008Xeon X54723.00 GHz1600Q4 2007Xeon X54823.20 GHz150WXeon X54923.40 GHzQ3 2008Core 2 Extreme QX9000 seriesQX977543.20 GHz12 MB150W1600Q1 2008
See also List of Intel microprocessors List of Intel Xeon microprocessors
References