AMD is quick to point out that Barcelona is about more than just four cores - they have made some changes to the underlying microarchitecture, namely:

• The processor core gets better SSE floating point handling; which means that SSE code will run up to twice as fast as before.
• The cache subsystems have been redone, with a 2MB third level shared cache being added to help with cache coherency.

"Rapid Virtualization Indexing" has been added to the existing virtualization support; and for motherboards that support it, Barcelona allows for a more efficient per core power management.

All of this is great news for data centers, as they can now pack twice as many Opteron cores into the same rack space - in many cases, even be able to upgrade just the processors (after flashing a new BIOS ofcourse) keeping the rest of the server unchanged.

I was glad to see that at least at the two socket level, AMD has decided on reasonable pricing.

For the standard series, $316 for a 75W TDP 1.9GHz Opteron 2347 quad core processor is not bad; currently a socket 771 Intel Xeon E5320 1.86GHz quad core processor retails for $282 - given similar performance and a lower TDP for AMD the $316 price point should be sustainable. At $389, the 2.0GHz Opteron 2350 (also with a 75W TDP) is a bit more expensive when compared to the $342 Xeon E5335. (Intel prices were taken today from a major web retailer)

The pricing is a bit more interesting in the "HE" High Efficiency range at the low end.

The $209 Opteron 2344 HE at 1.7GHz has a 55W TDP, and compares well price wise to the Xeon E5310 running at 1.6GHz at $354 - with this move AMD seems to be going for Intel's jugular; inexpensive 2P Xeon servers are currently Intel's volume server product, and here AMD is significanlty undercutting Intel; frankly the $255 Opteron 2346 HE at 1.8GHz still at a 55W TDP will look extremely attractive compared to the more expensive Intel part; and the $377 Opteron 2347 HE at 1.9GHz should be noticably faster for only a few more dollars.

Now before you think that AMD is willing to totally sacrifice processor pricing to regain market share, take a look at the pricing for the 8000 series of Opterons, the ones meant for 4P and 8P systems - they command a significant pricing premium over similarly performing Intel processors; mind you, 4P and 8P Intel platforms are fairly rare, and the motherboards are not inexpensive.

AMD is hoping to cash in on the advantage it should still have on 4P and 8P systems, and it will probably be able to do so - at least until Nehalem shows up with Intel's CSI (their functional equivalent to Hypertransport)

If you were wondering about the AMD Opteron processor model numbers, perhaps this slide from AMD's presentation will help: