InsaneTek has posted a review on the Kingston HyperX PC2-5400 1GB memory kit

The initial release of DDR2 was marked with high latencies, usually in the CAS 5 area. Corsair was the first to announce the "ultra low" latencies of high frequency DDR2 with their release of the XMS2-5400C4PRO. The timings were rated at 4-4-4-12, which is not all that low. However for DDR2, it's considered to be pretty good. Kingston quickly joined the games and produced the new HyperX2 line of memory. These modules had even lower latencies, running at 4-4-4-10. Although it's not much lower, it is still lower.

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