OCZ Flex XLC Water-Cooled CAS-3 DDR2-800 2GB Memory Kit

We first tested module overclockability using air-cooling, just to see how far we could take them before adding the more efficient water cooling element into the mix. As we mentioned before, the modules run at 800 MHz at CAS 3-4-4-15 @ 2.2V, which was our starting point.

Our first step was to go down in terms of latency. Surprisingly, the modules were able to clock down to CAS 3-3-3-12 @ 800 MHz at 2.2V, which is the lowest latency we've seen to date on a DDR2-800 module. The module would not run at 1T timing, but this is somewhat standard with most larger capacity modules. After an impressive start, we got to pushing up clock speeds. 

Stock Speeds - 800 MHz @ CAS 3-4-4-15

800 MHz @ CAS 3-3-3-12

At the same 2.2V voltage level, we were able to push our DDR2-800 modules up to an impressive DDR2-1142 level at CAS 5-5-5-15 latencies, nearly the same timings of OCZ's far more expensive Flex XLC DDR2 modules.

With one final push, we cranked the voltage level up to 2.3V and got even further. At this level, we were able to clock our modules up to DDR2-1155 speeds at CAS 5-5-5-15 latencies. Perhaps even more impressive is that we were able to run these modules also at DDR2-1066 speeds at CAS 4-4-4-12 latencies when at this voltage level. Our screenshot shows 4-4-4-15, but we were able to push this further down to -12 in our next set of benchmarks. 

1066 MHz @ CAS 4-4-4-15

1155 MHz @ CAS 5-5-5-15

While water cooling did improve our module temperatures by quite a lot, it did not help the overclockability much. We were not able to achieve higher overclocks or lower latencies with water cooling over traditional air cooling. However, when running at these ultra high levels, we would feel much comfortable for long term operation with a water cooling system opposed to air due to the much lower temperatures all around.

We should also note that every pair of modules is different, and we're not assuming that every pair of Flex XLC modules will overclock as well as ours did. These modules overclocked very well, delivering the same clock speeds and latencies as much more expensive modules.