One of the things I have learned about running SBS on under powered CPUs is where I can get the most bang for my buck. When I bought my server a couple of years ago it was a single CPU P3-700 with the potential of adding a second CPU. It worked for my very small network but every hour it maxed out the CPU for a short period doing some unspecified task related to sqlserver. Naturally the response time was poor during this period so I bought a second CPU off of eBay. The CPU was inexpensive so there wasn’t much risk. Amazingly this fixed the problem.
Naturally this lead me into preferring dual CPU systems. Entry level SBS systems use a single CPU. This setup is probably adequate for most small business with “few” client computers. The current crop of fast CPUs overcome the bottleneck I experienced. Businesses with a larger number of computers probably need a dual Xeon system. The availability of dual core systems probably expands the number of client computers a single CPU system can handle. I expect the Microsoft server products, SQLServer, ISA, and Exchange, to be very good at taking advantage of dual core systems. If this works as expected the low cost, dual core CPU should take market share away from the dual processor Xeon servers. Hmm…