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    <title>topic CPU comparison in Mobile and Desktop Processors</title>
    <link>https://community.intel.com/t5/Mobile-and-Desktop-Processors/CPU-comparison/m-p/275938#M5125</link>
    <description>&lt;P&gt;Comparison of an old intel pentium (Laptop in 1.7GHz and winXP_32) and a new i7 950 in 3.07 GHz (desctop Win Vista_64) : In most matlab applications and in matlab benchmarks, the new CPU ourperforms the old one (as it should be the case: faster 4-5 times). In one code however with nested for loops, the old one is faster by 50%. Anyone with a clue why this happens? Could it be logical?&lt;/P&gt;&lt;P&gt;&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;Note: The code includes interations of the form:&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;for k=1:Iter&lt;P&gt;&amp;nbsp;&lt;/P&gt; for i=1:n&lt;P&gt;&amp;nbsp;&lt;/P&gt;   for j=1:m&lt;P&gt;&amp;nbsp;&lt;/P&gt;      f(i,j)=...simple algebra of i and j without complex functions&lt;P&gt;&amp;nbsp;&lt;/P&gt;  end &lt;P&gt;&amp;nbsp;&lt;/P&gt;end&lt;P&gt;&amp;nbsp;&lt;/P&gt;end&lt;P&gt;&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;Matlab version 7.6. The same results (old cpu faster by 50%) no matter how many cores are enabled (multithreading using the matlab preferences) in the new CPU (either 1 or 4 or 8). &lt;/P&gt;&lt;P&gt;&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;Note 2: The question focuses mainly on how different CPUs realise the codes and not how a for-loop code could be optimised.&lt;/P&gt;</description>
    <pubDate>Mon, 29 Jun 2009 12:46:53 GMT</pubDate>
    <dc:creator>idata</dc:creator>
    <dc:date>2009-06-29T12:46:53Z</dc:date>
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      <title>CPU comparison</title>
      <link>https://community.intel.com/t5/Mobile-and-Desktop-Processors/CPU-comparison/m-p/275938#M5125</link>
      <description>&lt;P&gt;Comparison of an old intel pentium (Laptop in 1.7GHz and winXP_32) and a new i7 950 in 3.07 GHz (desctop Win Vista_64) : In most matlab applications and in matlab benchmarks, the new CPU ourperforms the old one (as it should be the case: faster 4-5 times). In one code however with nested for loops, the old one is faster by 50%. Anyone with a clue why this happens? Could it be logical?&lt;/P&gt;&lt;P&gt;&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;Note: The code includes interations of the form:&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;for k=1:Iter&lt;P&gt;&amp;nbsp;&lt;/P&gt; for i=1:n&lt;P&gt;&amp;nbsp;&lt;/P&gt;   for j=1:m&lt;P&gt;&amp;nbsp;&lt;/P&gt;      f(i,j)=...simple algebra of i and j without complex functions&lt;P&gt;&amp;nbsp;&lt;/P&gt;  end &lt;P&gt;&amp;nbsp;&lt;/P&gt;end&lt;P&gt;&amp;nbsp;&lt;/P&gt;end&lt;P&gt;&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;Matlab version 7.6. The same results (old cpu faster by 50%) no matter how many cores are enabled (multithreading using the matlab preferences) in the new CPU (either 1 or 4 or 8). &lt;/P&gt;&lt;P&gt;&lt;/P&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;&lt;P&gt;Note 2: The question focuses mainly on how different CPUs realise the codes and not how a for-loop code could be optimised.&lt;/P&gt;</description>
      <pubDate>Mon, 29 Jun 2009 12:46:53 GMT</pubDate>
      <guid>https://community.intel.com/t5/Mobile-and-Desktop-Processors/CPU-comparison/m-p/275938#M5125</guid>
      <dc:creator>idata</dc:creator>
      <dc:date>2009-06-29T12:46:53Z</dc:date>
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