Tweak3D - Your Freakin' Tweakin' Source!


Posted: October 25th, 2004
Written by: Adam Honek





Memory, Why DIMM 2 > DIMM 1?



Not everyone's wisdom is fulfilled in understanding why given memory is better than others (such as that from competing manufacturers) so before we discuss how the Ballistix PC3200 DDR faired in operation we will elaborate somewhat on this issue. Let us assume we are examining a comparison between two memory DIMM's both of type PC3200 DDR but which vary in latencies. Both reading & writing to RAM involves some form of delay normally referred to as latency, this is something influenced by timings in affect within the memory. Timings are part of the configuration data initiated upon computer bootstrap (a process where the BIOS checks and initially configures components). Lower timings mean less delay when performing memory operations, the key point to understand here however is that not all memory can be setup to use the fastest timings.

Above we introduced the example of comparing two memory DIMM's, now we will extend this more and provide names for these as a means of identification. DIMM 1 is generic and at PC3200 speed (200MHzx2) is rated at timings of 2.5-3-3-7, DIMM 2 is our Ballistix sample kit and at the same PC3200 speeds is rated at timings 2-3-2-6. Automatically we can see that DIMM 2 has lower timings than DIMM 1, in fact when combined they add up to 15.5 and 13 respectively. In this scenario DIMM 2 will operate faster by reducing the delay to access memory hence the CPU will be required to wait less of its own cycles. By logically piecing this together it should be understood that by lowering delays the system is able to respond much sooner to for example a fetch data call by the CPU. The end result is improved performance but this varies depending on how the software was programmed, i.e. if it heavily relies on memory usage. As a rule of thumb lower timings will always yield better system responsiveness so as a consumer it is worth not overlooking this aspect upon purchase.


Next Page: In Operation

  • News
  • Forums
  • Tweaks
  • Articles
  • Reviews