Latency, Overclocking, And Bandwidth
Today’s comparison is more of a race than a value analysis, so we begin our tests by finding the highest stable memory speed supported by our platform for each memory kit.
The only three memory kits able to reliably exceed the DDR3-2000 barrier are those already rated to do so. G.Skill goes a step further by also exceeding DDR3-2133, which is the next full step beyond DDR3-1866 in a market where standard parts come in 266 MHz increments. The ability of several sets to exceed DDR3-2000 also adds a higher setting for our latency tests.
|Best Timings at 1.65 V|
|G.Skill DDR3-2000 CAS 9|
|PQI DDR3-2000 CAS 9|
|Super Talent DDR3-2000|
CAS 8, WP200UX4G8
|Team Group DDR3-1600 CAS 8|
|Patriot DDR3-1600 CAS 8|
|Crucial DDR3-1333 CAS9|
|Kingston DDR3-1600 CAS 8|
|PNY DDR3-1600 CAS 8|
Not only is G.Skill able to reach exceedingly-high speeds, these modules pushed CAS 7 latency at DDR3-2000. PQI’s hard-to-find parts are not far behind, while Super Talent reached CAS 7 at DDR3-1866.
Old timers who think DDR3 latency numbers sound high must be reminded of how these apply to response time. Because latency is measured in memory clock cycles that are the inverse of frequency, DDR3-1600 CAS 8, DDR2-800 CAS 4, and DDR-400 CAS 2 would all have the same response time. Half of today’s samples are quicker than DDR3-1600 CAS 8.
G.Skill had the best latencies at DDR3-2000, so its lead in Sandra is unsurprising.
Super Talent leads the latency chart at DDR3-1866, and is similarly rewarded in Sandra Memory Bandwidth.
G.Skill and Super Talent tie in Sandra Bandwidth at DDR3-1600, which makes some sense only if Super Talent’s lower tRAS is a match for G.Skill’s lower tRP.
Super Talent leads at DDR3-1333, but it’s not like anyone actually plans to run this memory that “slow.”