Review Index:

Intel Pentium 4 3.4 GHz Prescott Processor Review

Subject: Processors
Manufacturer: Intel


The Prescott core processors were released with the 3.2 GHz revisions along with the 3.4 GHz versions of the Pentium 4 Extreme Edition CPUs.  The new core from Intel was met with mixed reviews, as the benchmarks showed the core to be less than impressive compared to its older, Northwood cousin.  As the frequency starts to ramp up, the new core changes will be more effective, but are we there yet?

Prescott Quickie

The Prescott core change for the Pentium 4 line introduced a few changes to Intel's processor line.  First, the Prescott is a move from 0.13 micron technology to 0.09 micron.  Where the Northwood processors sported 512 KB of cache, the Prescott has upgraded to a full 1 MB of cache on-die.  Along with this upgrade, Intel added new SSE3 instructions to the P4 line within the Prescott CPUs. 

The pipeline to the P4 was changed slightly as well.  There are now more stages in the pipeline, which has both a positive and negative effect on performance.  Without getting into the details that you would encounter in a college level engineering class, think of pipeline stages as positions in an automatic carwash.  The more stages, the less you have to do at each stage.  The problem is that when a branch code is encountered in software, if the prediction device didn't guess correctly, the processor will have to start over on the information to be computed.  With deeper pipelines, this means that 'branchy' code can lose performance over short depth pipes for simply that reason.  There are of course a lot more details and exceptions to this rule, but that is the overall basics.

 What Intel is banking on now, is that their increasing frequency, courtesy of a longer pipeline, will counter the disadvantage of the additional stages.  At 3.2 GHz they had not quite reached that level, but is 3.4 GHz fast enough for it yet?

 For this review, we'll go ahead a look at our benchmarks and see what we come up with at the end of it all.