Overclocking
Overclocking tests were carried out using the maximum stated voltages for the modules, except in the case of the OCZ Reaper HPC PC2-9200 modules where the Enhanced Voltage Policy allows for up to 2.35V, to give results representative of what can be achieved without voiding the warranty.
This means that the Corsair DOMINATOR XMS2-10000 was run at 2.4V; the Kingston HyperX KHX9600D2K2/2G and OCZ Reaper HPC Edition PC2-9200 at 2.35V; the CellShock DDR2 1000 at 2.3V; and the G.SKILL F2-6400CL4D at just 2.1V.
The Corsair was run using the included DOMINATOR Airflow fan, while the other modules were cooled passively.
Testing was carried out using 3-3-3-9, 4-4-4-12 and 5-5-5-18 latencies, with the maximum stable speed over a 30-minute stress-test recorded for each module.
At
these low latencies, the
Corsair is able to take a 60MHz lead as the only module to break
900MHz. The Kingston, OCZ and Cell Shock modules were tightly
bunched in the mid-800s.
The G.SKILL's low voltage is presumably the cause of its poor overall
performance at 3-3-3-9, 700MHz being the best it could offer,
despite
having relatively low latencies at stock.
With
the timings pushed up
to 4-4-4-12, the modules all start to stretch their
legs and
we see a big jump in speeds.
The Corsair extends its lead to 100MHz, while the Kingston, OCZ and
Cell Shock are again grouped tightly together, but all
reaching
1100MHz.
As before, the G.SKILL lags
behind, now by 200MHz.
And
finally to 5-5-5-18, where the G.SKILL at last gets
to break the 1GHz barrier.
The big news, however, is that the Corsair's lead has now shrunk
to practically
nothing.
The OCZ Reaper has closed
to within 10MHz of
the Corsair, despite giving away 0.05V, lacking active cooling
and being £330 cheaper!
And
the Kingston and CellShock modules aren't far behind either.
Summary
As you would expect, the Corsair DOMINATOR XMS2-10000 modules come out on top at each set of timings, although its ultimate MHz crown at 5-5-5-18 latencies is taken by a rather slim margin.
Its 4-4-4-12 results are more impressive but we can't stop thinking about that £469 price-tag.
G.SKILL trails well behind the pack at every step of the way. It may be the cheapest but it shows. Increased voltages could certainly help but risk voiding the lifetime warranty.
The Kingston, OCZ and CellShock modules are hard to separate throughout, with the OCZ Reaper HPC Edition PC2-9200 modules just edging ahead at 5-5-5-18.
As always, these results are only representative of the samples we test. Your own results could and most probably will vary from our own but since all the modules are subject to variance, we feel that our testing does gives a good general overview of what is possible in high-performance memory.