PC133 SDRAM Roundup - April 2000

If you remember back to our PC100 SDRAM Comparison from March 1999 we had a couple modules that could actually hit the 133MHz mark with reasonable success, so why is there even a need for newer PC133 SDRAM?

Other than the obvious fact that most PC100 SDRAM couldn’t even reach the 129MHz mark much less the 133MHz level, the modules that managed to reach 133MHz did so at a CAS Latency of 3 clocks.  The CAS Latency, or Column Access Strobe Latency helps to define how quickly memory can be accessed, and having a lower CAS Latency value should theoretically increase performance.  But by how much?

In order to answer that question we ran a few benchmarks illustrating the performance difference between running PC133 SDRAM at 133MHz/CAS 2 and 133MHz/CAS 3 on our ASUS P3V4X VIA Apollo Pro 133A test platform.

We get less than a 2% increase in performance in CC Winstone 2000 when decreasing the memory timings to CAS 2 on our PC133 setup.  This is mainly because Content Creation applications tend to reside within the L2 cache of a processor, and in the case of our Pentium III test CPU, the full speed on-die 256KB of L2 cache is enough for most of the CC Winstone applications.

Quake III Arena exhibits a 3% increase in performance when moving to CAS 2, it’s not a tremendous increase but it is something.