When looking at the AMD Phenom 9500 under Linux, we had found this processor had posed a number of issues from kernel panics to other troubles when running Ubuntu 7.10 with the Linux 2.6.22 kernel. Once, however, upgrading to Ubuntu 8.04 with the Linux 2.6.24 kernel these problems had vanished and we were pleased by this native quad-core desktop processor from AMD. Released a month prior to the first Phenom desktop CPUs were the quad-core Opteron 2300 "Barcelona" processors. We hadn't looked at any AMD Barcelona processors at that time, but today we finally have our hands on two of the new AMD Opteron 2356 server/workstation processors. The Opteron 2356 CPUs come clocked at 2.30GHz, and is a revision B3 Opteron meaning that it has a proper fix for the TLB erratum -- this model was introduced only earlier this month. We have benchmarked the new Opteron 2356 in both single and dual CPU configurations and have compared the results -- under Linux -- to two of Intel's quad-core Xeon processors.