HP's 2P DL385 Barcelona server frags HP DL580 4P Quad-Core Xeon server
A 2P DL385 G5 2.3GHZ Barcelona Opteron server (total 8 cores) can handle 174 Heavy Users in HP's benchmark.
A 4P HP 2.3GHZ Opteron blade server can handle 301 heavy users .
In comparison, a 4P 2.9 GHZ Intel Quad-Core Xeon Dl580 G5 server (total 16 cores) does 233 Heavy users.
The result: a 4P 2.3GHZ Opteron blade frags a 4P 2.9GHZ Quad-Core Xeon server by a whopping 29.2%.
But this is not the end of the story. If you look at the number of light users, the HP DL580 G5 4p Quad-Core Xeon (total 16 cores) can do 386 Light Users. The HP DL385 2P 2.3GHZ server (2.3GHZ) can handle 380 Light Users.
It is obvious that with a slightly faster 2.4GHZ Opteron, the 2P DL385 will frag the 4P DL580. In other words, one Opteron quad-core CPU frags two Xeon quad-core CPUs in an SMP configuration.
It is clear that Intel CPUs are only good for single threaded 1P operation. The fact that a 2P-8 core Opteron server frags a 4P-16 core Xeon server is an old story. With 16 Xeon cores hanging on a FSB, each Xeon core gets the bandwidth of a 80486.