- Contents - - Introduction - First Impressions - Specification - Installation - Memory, Why Memory A > Memory B? - In operation - Test setup - Test methodology - Test results - Conclusion

Memory, Why Memory A > Memory B?

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 PC2-6400 DDR2 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 PC2-6400 DDR2 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 whereby 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 DIMM's, now we will extend this more and provide names for these as a means of identification. DIMM 1 is generic and at PC2-6400 speed (400MHzx2) is rated at timings of 5-5-5-15, DIMM 2 is our Ballistix sample kit and at the same PC2-6400 speeds is rated at timings 4-4-4-12. Automatically we can see that DIMM 2 has lower timings than DIMM 1, in fact when combined they add up to 30 and 24 respectively. In this scenario DIMM 2 will operate faster by reducing the delay to access memory hence the CPU will be required to idle less of its own cycles. By logically putting 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 issued by the CPU. The end result is improved performance but the true extent of 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.

The goal to achieving best memory efficiency is running at the highest possible frequency while at the same time maintaining the lowest RAM timings. There is always a balance to these two and only stability tests on each given system yield the exact answer.

Next Page: In operation