The hardware virtualization features in AMD's K10 are quite impressive, but we'll discuss them later. This confirms our and Intel's assumption that the K10 will probably make the largest impact as a very potent HPC chip. Combine this with the fact that the K10 is running at only 2.3 GHz, and we can conclude that the memory subsystem (Load/store unit, L1, L2, Northbridge) of the K10 is simply (vastly) superior compared to the Athlon 64s and to the quad Xeon. Ron Myers of AMD claimed that the difference is now already greater than 42%. So most of the 42% advantage is probably due to K10's better Northbridge and better use of DDR2. As has been shown numerous times, the current Athlon 64 X2/Opteron architecture is not able to use the extra bandwidth that DDR2 gives. We reported in our Barcelona architecture article that the AMD K10's Northbridge is set up to handle higher bandwidth than the current AMD chips. This puts AMD's claim that the best "K10" (most likely at 2.3 GHz) will be 42% faster than the Xeon x5355 in Spec FP rate in the right perspective. It is no surprise that the quad socket Opteron 8220 is about 34% faster than the Xeon x5355 (and we are ignoring the probably inflated result of 184 you can get with the Sun Studio Compiler). That means that the quad Xeon 2.66 GHz is only about 32% faster than its dual core brother at the same clock speed, another clear indication that the dual Xeon x5355 scores are seriously limited by memory bandwidth. If we take a look at the best dual core Xeon 5150 (2.66 GHz) score, it gets a score of 78.2. The result is that the dual Xeon x5355 (eight cores) is heavily bottlenecked by a lack of bandwidth and hardly faster than the dual Opteron 2220SE (four cores) in CPU FP2000 rates. As we use eight cores in total instead of four, the bandwidth demands of the SpecFP benchmark also double.ĪMD vs. If we compare a dual quad core Xeon (x5355) with a quad socket dual core Opteron, the bandwidth of the AMD platform doubles while the bandwidth of the Intel system stays the same. In a two socket machine, the Opterons have roughly twice as much bandwidth as with one socket, so SpecFP rate is basically the ideal benchmark to show the benefits of AMD's NUMA platform. So running several of those benchmarks will only increase the bandwidth needed. SpecFP rate is nothing more than several SpecFP benchmarks running completely separate from each other, and it is well known that SpecFP is a bandwidth intensive benchmark. Intel Quad Core Performance Overviewįirst of all, it should be noted that Spec FP2000 rate and Spec FP2006 rate are already running better on the dual core Opteron than on the dual core Xeon "Woodcrest". Let us first look at the dual socket systems, as we try to find more precise SPEC (base) numbers:ĪMD vs.