You may well have seen by now that SQL 2012 bring with it a big change, moving from “Per CPU” to “Per Core” licensing. (Read more here.)
Well there’s one more bit that hasn’t been widely announced but can make a fair difference in certain scenarios, and that is the “Microsoft SQL 2012 Core Factor Table”:
What?
There is a minimum of 4 core licenses per physical processor so the above table shows that:
1 x Single Core = 4 Cores
2 x Dual Core = 4 Cores
which fits the model. However you can see that there is special dispensation for certain AMD processors where each physical core is worth just 0.75 cores when it comes to SQL. S0 that means:
6 physical cores on an AMD 32XX CPU = 4.5 SQL Cores*
*I believe this would be rounded up to 5…and you have to buy in multiples of 2 so doesn’t alter anything…but if you have an 8 core CPU of the above kinds, you’d then only need to buy 6 SQL cores (8*.75=6).
This does add an extra bit of complexity to correctly designing an SQL solution but hey, that’s what us licensing gurus are for right? 
I do wonder how this will affect decisions when companies are speccing up hardware for SQL deployments. Will previously 100% Intel houses start looking at AMD chips for the SQL cost savings they can bring?
I don’t see how anyone in their right mind would consider AMD for SQL 2012 until AMD CPUs get a radical overhaul. A maxed out 2×16 core Opteron 6282SE SQL server pumps about as much SQL data as an 2×6 core Intel Xeon X5690. Even with the 0.75 factor, it’s not even CLOSE. Going AMD seems like an awful idea right now. Check out http://sqlserverperformance.wordpress.com/2012/01/03/new-tpc-e-benchmark-for-hp-dl385-g7/ for what I’m talking about.
This helps AMD be a little more competitive, but it far from closes the gap in my opinion based on the benchmarks I have seen so far. I wish AMD was doing better on the high end, to help keep Intel focused on pushing the release cycle.
Core factor table was supposed to counterbalance CPU power in case of multi-core chips. When i see 1 x Single Core(ie Intel Pentium III) = 4 Cores. Are you kidding ?!?!
The only purpose of this figure is to force company to trash their old assets, not counterbalance CPU power. When i see other vendor’s core factor table like IBM, ORACLE that says 1 single core CPU = 1 Core, from my point of view, with this metric and + 25% for the CAL Price, Microsoft try to swindle its customers.