Legit Reviews posted a review on the B3 stepping of the AMD Phenom X4 processor
When the AMD Phenom series of processors launched back on November 19th, 2007 no one could have expected just how rough things were about to get for AMD. AMD has fixed the problems with a new B3 stepping of Phenom. All of the new Phenom B3 steppings will be named with the nomenclature of what AMD is calling the '50 series' of processors. The four new AMD Phenom X4 processors that AMD is announcing today are the 9550 (2.2GHz), 9650 (2.3GHz), 9750 (2.4GHz) and 9850 Black Edition (2.5GHz).AMD Phenom X4 9850 Processor Review
"The new AMD Phenom X4 50-series of processors is how Phenom should have launched back in November of last year. This stepping of Phenom doesn't offer higher performance versus the older Phenom B1 and B2 steppings, but does remove the TLB erratum that caused many consumers to skip over Phenom when considering a platform for their next system. Those that already have an AMD Socket AM2 platform now have a solid upgrade path to look forward to...