SSE2 makes Opterons slower than Athlon XPs

A JAPANESE JOURNALIST said that an investigation he&#8217;s conducted shows that using SSE2 multimedia extensions with the AMD Opteron makes the microprocessor slow to a crawl.Takeo Noguchi. at ASCII Plus Magazine, analysed the Opteron 242 as a microprocessor for a single chip machine, and said that a 1.6GHz chip, according to AMD< slightly outperform a Xeon/Pentium 4 running at 2.8GHz.

He told the INQUIRER that he measured the execution time to encode DV-format AVI files to MPEG, WMV, Divx and Xvid. He found that for encoding DivX and Xvid, Opteron 242&#8242;s performance is roughly equivalent to a Pentium 4-2.8GHz, which matches the expectation from SPEC int/fp results.

But, he added, using well known JapaneseMPEG 2 encoding software TMPGenc ((http://www.pegasys-inc.com/), the Opteron&#8217;s performance is a staggering 30% lower than a Pentium 4-2.8GHz.

He said: &#8220;At first I supposed it was because TMPGEnc is thoroughly optimised for the Pentium 4&#8243;.

But he checked the results from SiSoftware Sandra 2003, and found to his surprise that its multimedia integer performance is much lower than the Athlon XP, the architectural cousin of the Opteron.

His results are as follows:

Sandra Multimedia Int

Opteron 242 (1.6GHz) 6300

Pentium 4-2.8GHz 11148

Athlon XP-2600+ 11614

But it&#8217;s not all bad news for the Opteron. He said that well known Japanese archiving software GCA (http://www.emit.jp/gca/gca.html) compresses WAV files a staggering 50% faster than P4-2.8GHz, equivalent to a Pentium 4.4GHz chip, if such a beast existed.

Source : Inquirer