As you can see from the benchmarks, the FX-55 performs better then the 4000+ on most of the bench marks. However, the 4000+ still performs pretty well. At time of release of the CPUs, the FX-55 is priced $200 more then the 4000+. So if you are looking for the absolute best CPU you can get, and have some extra money, you won't be disappointed by the FX-55. If you are looking for a good CPU to upgrade to, and are on a budget, The 4000+ is some good bang for the buck.

The Retail box package of the FX-55 and 4000+ will have a 3 year warranty directly through AMD. The OEM package does not come with a warranty through AMD, all warranties on OEM have to go through your reseller. Make sure you understand what warranty you are getting before you purchase the chip.