X-bit labs

AMD Phenom Changes Stepping to B3: TLB Bug – in the Past (page 2)

Category: CPU

by Ilya Gavrichenkov

[ 03/26/2008 | 09:00 PM ]

AMD Phenom X4 9850 Black Edition

AMD offered us their Phenom X4 9850 Black Edition processor to check out the performance and features of the new B3 processor stepping. It is a new top of the line representative of AMD’s quad-core processor family that is designed to work at 2.5GHz clock frequency, which is 200MHz higher than what the top processor on B2 stepping used to support. This way AMD finally managed to push the clock speeds of its quad-core processors to the level of the youngest Intel Core 2 Quad CPUs. However, this frequency increase results not from the improved frequency potential of the new processor stepping, but from the more advanced production process. That is why the new processors with 2.4-2.5GHz clock speeds also boast higher TDP of 125W.

Besides increase clock frequency, Phenom X4 9850 processor has one more unique distinguishing feature: the frequency of the built-in North Bridge has also been raised to 2.0GHz. This frequency is very important for the L3 cache and DDR2 SDRAM memory controller. That is why we can expect Phenom X4 9850 to work more effectively with the memory subsystem than its predecessors. However, it didn’t really affect the formal specs of the supported memory. Phenom X4 9850 works with dual-channel DDR2-533/667/800/1066 SDRAM and supports Ganged and Unganged modes that we have already discussed in our previous articles.

The complete list of Phenom X4 Black Edition specifications is given below:

It is important to point out that the embedded North Bridge working at 2.0GHz frequency is an exclusive feature of AMD Phenom X4 9850. All other Phenom processors including the ones using new B3 stepping have their North Bridge working at 1.8GHz frequency. The same is true for the HyperTransport 3.0 bus frequency: in Phenom X4 9850 it works at 2.0GHz, while all other quad-core AMD processors use a 1.8GHz bus.

To make things a little bit clearer in terms of available AMD Phenom X4 processor modifications, we would like to offer you another small table:

Note that since Phenom X4 9850 belongs to the Black Edition series, it boasts another distinguishing feature: unlocked clock frequency multiplier offering a lot of overclocking flexibility. By the way, AMD has no plans to launch a non-Black Edition modification of this CPU yet.

Since new B3 processor stepping has no principal differences from B2 processor stepping other than the TLB-bug fix, all mainboards compatible with the old Phenom X4 can also work with the new processor modifications.