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AMD Beats Intel in Power-Efficiency Study
Ted Samson writes "AMD Opteron servers proved up to 15.2 percent more energy-efficient than those running Intel Xeon in a server-power-efficiency test performed by Neal Nelson and Associates, InfoWorld reports. That translates to annual electricity savings between $20.29 per server and $36.04 per server, depending on the workload, the study concluded. The benchmark tests were conducted on similarly configured 3GHz systems running Novell SUSE Linux, Apache2, and MySQL."
Both systems had 3.0Ghz CPUs and similar amounts of RAM. But did they offer the same performance? If both servers were being pushed 100% would one be able to server more users than the other? If the servers were never pushed to 100% then the test is not really a like-with-like comparison. I imagine that one CPU performs better than the other (and I'd expect right now that's the Intel one). Perhaps a 2.66Ghz vs 3.0Ghz test is closer to the same performance?
The reason why is because the Woodcrest Xeon is the only 3GHz Xeon that Intel made, and for some reason they decided to standardize this test on "3.0 GHz". Since everybody knows that AMD outperforms Intel on a per-GHz basis, it does lead one to wonder why they chose that particular metric, but honestly no matter what metric they chose people would complain.
.5GHz slower/faster than XXXX's". It's a lose-lose situation for the tester.
For one, AMD and Intel don't release their new chips on the same date, so one side can always complain "that's not our newest stuff" or "yeah, but just wait until our next generation". If you wait for same generation, same CPU frequency chips from both manufacturers before you do a benchmark, you're going to be waiting a while - it'll never happen. And if you pick a "performance class" to set your benchmark on, somebody will complain "yeah but XXXX's chip is
Also above there is a discussion about chipsets / power supplies / etc. Again nearly impossible to standardize on this stuff as well. Obviously there is no motherboard that is identical in every regard except the processor that it accepts. Another thread talks about the memory controller for Intel being off-chip vs. on-chip for AMD - so right there you have to go beyond the CPU and include more platform to make a "fair" comparison. Even if they standardized on a power supply, people can argue that the system that pulls less power doesn't need the larger power supply and could save more power (less loss to inefficiencies) on a smaller unit. So do you run the recommended unit for the server or run the same, possibly wrong power supply for both?
My overall point being that in for somebody to do any kind of test like this, they need to setup some base rules. I don't know why people complain so much - they provide all the criteria they chose and did a comparison based on that. If that doesn't answer a question you had, do it yourself or go to another benchmark. Don't complain that the test is invalid because your chip of choice didn't win. For this benchmark, power consumption for 3.0 GHz servers under "real world" conditions (not idle, not pinned, running various applications from databases to web servers), AMD won. Get over it.