Intel is getting ready to ship out Celeron D processors with a new stepping, being one of the latest NetBurst processors to get the update. The Celeron D with model numbers 326, 331, 336, 341, 346 and 351 will all be upgraded from the E-0 stepping to the updated G-1 on December 2nd.
The G-1 core will use less lead to be compliant with the European Reduction of Hazardous Substances (RoHS) and will add two instructions to make Intel's EM64T fully compatible with AMD's AMD64 technology.
Intel is adding the LAHF and SAHF AMD64 instructions to its own 64-bit instruction set architecture. It has been alleged that they were missing from the original EM64T specification because the AMD documents used by Intel's engineers pre-dated AMD's addition of the two mnemonics.The Pentium 4 will get this update on November 14th while the Xeon DP processors will get it two weeks later on November 28th. According to Intel consumers will only need a BIOS update to use these new processors.
LAHF and SAHF two instructions copy content back and forth between a 64-bit x86 processor's status flags and its AH register.