Results Summary and the Ratings
Benchmark Summary: Corsair's TWIN2X1024A-5400UL modules bested the Kingston modules in each and every one of the benchmarks we ran, but the margin of difference was usually less than one percent. Although the Corsair kit was able to reach lower latencies overall (3-2-2-4 vs. 3-4-4-4) this didn't result in any major gains. Both of the kits overclocked well, and we feel that we were more limited by our setup than the memory. In fact, it's quite possible we could have reached much higher speeds with an unlocked CPU, where we could have lowered the CPU multiplier and increased front side bus speeds even further.
Corsair XMS2 TWIN2X1024A-5400UL:
Corsair's TWIN2X1024A-5400UL performed admirably, as we discussed in the performance analysis. Again and again they outperformed a similar memory kit from Kingston, although the performance deltas were actually quite small. These sticks lived up to their Ultra-Low Latency label, as hitting 3-2-2-4 at 337MHz has been mostly unheard of with DDR2. You can also expect to get a real boost by overclocking these modules - we were able to hit DDR798 and felt there was still more headroom left. Pricewise, Corsair generally falls a bit higher on the scale, and this kit is no different. Average price online appears to be around $330, but for those who simply must have the best, price is no option. We're giving the Corsair XM2 TWIN2X1024A-5400UL a 9 on the HotHardware Heat Meter and our highest praise, a HotHardware.com Editor's Choice Award.
Kingston HyperX KHX6000D2K2/1G:
While Kingston's KHX6000D2K2/1G kit technically "lost" each of the head-to-head contests with Corsair, the difference in performance was so small it would be imperceptible during real-world use. We were pleasantly surprised by the outcomes, especially during the lowest-latency testing. At first, we were a little concerned that the RAM wouldn't go lower than 3-4-4-4, but as we have shown, this did not seem to effect the overall breakdown of the scores. Kingston's memory also overclocked well, reaching as high as 798MHz before we peaked. As this kit is actually rated for standard operation at 750MHz, this doesn't sound like a huge increase, but again we point out that the lack of ability to continue raising speeds was a fault of the CPU/Motherboard and not the memory. Another factor that may swing buyers will be the price: Kingston's memory kit is slightly less expensive than Corsair's. We're giving the Kingston HyperX KHX6000D2K2/1G an 8.5 on the Heat Meter.