14 DAY TRIAL // It is customary in the central processing units manufacturing industry to release a processor featuring some basic improvements and then after some time to launch a new variant of the same processor which integrates a set of upgrades over the previous design. This process is called "stepping up" a processor and it is done at a large scale not only by the processor manufacturers, but by other companies active of the computer hardware market like mainboard and video cards manufacturers, even in those cases we are talking about "revisions".
Intel has just announced such a measure as their quad core Clovertown processor family which is intended to be used in servers received a new stepping from B3 to G0. This new Clovertown variant comes with some design improvements like reduced power consumption and other abilities. Affected by this change are all processors from the 1.6GHz to 2.6GHz range which are dual die, dual core CPUs featuring 8MB of total second cache memory split between the two 4MB caches. The new processors will become available on the market since the 4th of October, 2007. The manufacturing company announced no details about the power reduction features of the new Clovertown central processing units with the G0 stepping, but said that they will feature a new and enhanced virtualization engine.
The new virtualization engine will come with a new version of Task Priority Register (TPR for short) for the Advanced Programmable Interrupt Controller (APIC) which should translate into a better task priority assignment and execution as higher priority tasks must be executed before low priority tasks are processed. From the software's and users' point of view this is a highly desirable feature as it allows the entire system to be more responsive. Apart from these features the G0 stepping comes with some new string manipulation technologies which are basically related to the IN and OUT operations that occur when moving data from peripherals to the processor and back. G0 will also introduce a new CPUID code which is used to distinguish between one type of processor and another and while the previous iteration, B3, used the 06F7 code, G0 comes with 06FB. Some software utilities will need the new stepping code in order to be able to access the detailed information available for this processor family.
Affected by this new revision are all the processors from the Clovertown line of products like the X5355, E5345, E5335, L5320 and E5310 which operate at 2.66/1333GHz, 2.33/1333GHz, 2.0/1333GHz, 1.86/1066GHz and 1.6/1066GHz respectively. According to the news site tgdaily, the product names will stay unchanged as will the TDP ratings of 120, 80 and 50 watts. After the official release of the G0 stepping the older B3 processors will continue to be manufactured and shipped for some time, until the production level for the new processors is high enough to cover the entire market demand.