In the past I was somewhat biased towards 2-socket servers for virtualization - which was due to the results of some testing we did. I had of course realized over the past year or so that things had changed and the 4-socket servers were now more competitive. So when I ran the series of chats on Selecting a Server for Virtualization, I decided that it was a good opportunity to re-run some of those exact same tests with the brand new R900 that had arrived in the lab. I posted the results on a TechCenter page so you can see the full results, but the short summary is that the R900 stacks up as more efficient than the 2950 we tested in the previous paper. The R900 showed 10 to 23 percent better performance per watt than the older 2950. The question that remains is how would the R900 compare to a current generation 2950?

Todd