limited edition Deneb-based processor to extreme overclockers and partners. Fewer than 100 were manufactured. The "42" officially represents four cores running at 2 GHz, but is also a reference to the answer to life, the universe, and everything from The Hitchhiker's Guide to the Galaxy. Four AMD K10 cores Models: Phenom II 42 TWKR Propus (45 nm SOI, quad-core) Four AMD K10 cores harvested from Deneb with L3 cache disabled ISA extensions: MMX, Enhanced 3DNow!, SSE, SSE2, SSE3, SSE4a, ABM, NX bit, AMD64, Cool'n'Quiet, AMD-V Memory support: DDR2 SDRAM up to PC2-8500 (DDR2-1066 MHz), DDR3 SDRAM up to PC3-10600 (DDR3-1333 MHz) (Socket AM3 only) Models: Phenom II X4 840 and 850 Heka (45 nm SOI, tri-core) Three AMD K10 cores using chip harvesting technique, with one core disabled L1 cache: 64 KB instructions and 64 KB data per core L2 cache: 512 KB per core, full-speed L3 cache: 6 MB shared between all cores Memory controller: dual channel DDR2-1066 MHz (AM2+), dual channel DDR3-1333 (AM3) with unganging option ISA extensions: MMX, Enhanced 3DNow!, SSE, SSE2, SSE3, SSE4a, ABM, AMD64, Cool'n'Quiet, NX bit, AMD-V Socket AM3, HyperTransport with 2000 MHz Power consumption (TDP): 65 and 95 Watt First release 9 February 2009 (C2 Stepping) Clock rate: 2500 to 3000 MHz Models: Phenom II X3 705e - 740 Callisto (45 nm SOI, dual-core) Two AMD K10 cores using chip harvesting technique, with two cores disabled L1 cache: 64 KB instructions and 64 KB data per core L2 cache: 512 KB per core, full-speed L3 cache: 6 MB shared between all cores Memory controller: dual channel DDR2-1066 MHz (AM2+), dual channel DDR3-1333 (AM3) with unganging option ISA extensions: MMX, Enhanced 3DNow!, SSE, SSE2, SSE3, SSE4a, ABM, AMD64, Cool'n'Quiet, NX bit, AMD-V Socket AM3, HyperTransport with 2000 MHz Power consumption (TDP): 80 Watt First release 1 June 2009 (C2 Stepping) Clock rate: 3000 to 3500 MHz Models: Phenom II X2 545 - 570 Regor (45 nm SOI, dual-core) Two AMD K10 cores Some are chip harvests from Propus or Deneb with two cores disabled Most Regor-based processors feature double the L2 cache per core (1 MB) as other Athlon II and Phenom II processors. ISA extensions: MMX, Enhanced 3DNow!, SSE, SSE2, SSE3, SSE4a, ABM, NX bit, AMD64, Cool'n'Quiet, AMD-V Memory support: DDR2 SDRAM up to PC2-8500, DDR3 SDRAM up to PC3-8500 (DDR3-1066 MHz) (Socket AM3 only) Models: Phenom II X2 511 and 521 Athlon