Recent tests by Neal Nelson & Associates, an independent computer performance consulting firm, have reported that in 36 of the 57 cases tested an AMD Opteron based server delivered better power efficiency than a comparably configured Intel Xeon based server. The tests were performed on servers configured with 2, 4, 6 and 8 gigabytes of main memory at various transaction processing load levels.
Recent tests by Neal Nelson & Associates, an independent computer performance
consulting firm, have reported that in 36 of the 57 cases tested an AMD Opteron
based server delivered better power efficiency than a comparably configured
Intel Xeon based server.
The tests were performed on servers configured with 2, 4, 6 and 8 gigabytes of
main memory at various transaction processing load levels. The results show that
for certain configurations and at certain load levels the Intel Xeon based
server was 2.4 to 11.7 percent more power efficient while in other cases the AMD
Opteron based server was 9.2 to 23.1 percent more power efficient. In addition,
when the systems were idle and waiting for transactions to process, the AMD
server was 30.4 to 53.1 percent more power efficient.
Power consumption while the servers are idle is particularly significant since
many servers spend most of their time waiting for work. A November 16, 2006
press release(1) from IBM quotes a report by the Robert Frances Group(2) which
states that on average servers in datacenters are idle 80 to 85 percent of the
Other observations that can be made from the test results include:
1) Larger memory configurations deliver both higher throughput and better
power efficiency, 2) Intel’s power efficiency advantages decrease as memory size
increases, 3) AMD’s power efficiency advantages increase as memory size
increases, 4) For primarily calculation type workloads, the Xeon delivers 8.0 to
14.0 percent higher peak throughput, and 5) For primarily disk I/O intensive
workloads the Opteron delivers 11.3 to 19.4 percent higher peak throughput.
These test results were collected by Neal Nelson’s second generation Server
Power Efficiency Benchmark. This test is a client server benchmark where world
wide web transactions are processed against a server configured with Novell’s
SUSE Linux Enterprise Server, the Apache2 web server software and the MySQL
relational database. The benchmark subjects a server to various user loads,
reports the power consumed at each load level and provides meaningful
comparisons of server power usage.
These tests were not financed or sponsored by any company or group. Neal Nelson
conducted these tests in response to a statement made by Intel CEO Paul Otellini
in a July 18, 2007 analyst conference call. During that call Mr Otellini
referred to Intel’s "lead in power efficiency". Neal Nelson decided to use his
company’s benchmark toolset to determine if Intel actually had a lead power
efficiency. "It appears that Mr. Otellini’s statement is inconsistent with the
test results," observed Nelson.
Nelson’s firm has a long history of data processing consulting to some of the
world’s largest computer customers including the U.S. Army, U.S. Navy, the
Internal Revenue Service, McDonalds, WalMart and Federal Express. Nelson’s
benchmarking laboratory is available to commercial and government users for
independent computer performance tests.
A link to a white paper with more detailed information is available on the world
wide web at