With the introduction of AM2 socket by AMD all new high-end PCs are finally using DDR2 memories. Right now the standard DDR2 speeds are 533 MHz, 667 MHz and 800 MHz, but Corsair was one of the first manufacturers to release 1,066 MHz models. These models are not only targeted to both Intel and AMD over clockers but also to regular users that have an Intel CPU running externally at 1,066 MHz and want to match the memory with the CPU external speed to achieve the maximum performance your system can deliver. Corsair has released a 1 GB kit (TWIN2X1024-8500C5, 2x 512 MB modules) and a 2 GB kit (TWIN2X2048-8500C5, 2x 1 GB modules), both with 5-5-5-15 timings. Let’s see how the 2 GB kit performs.
For the regular user that does not over clock his/her system, the main advantage of DDR2-1066 memories would be using them with Intel CPUs running at 1,066 MHz externally – for example, the new high-end Core 2 Duo and Core 2 Extreme CPUs. If you use DDR2-800 memories with these CPUs, the communication between the CPU and the memories will be taken only at half of the maximum speed it could be used. The problem, however, is that only very few socket 775 motherboards accept DDR2-1066. On almost all socket 775 motherboards your DDR2-1066 modules will run as if they were DDR2-800, even on the latest ones based on the new Intel 975X chipset.
Of course you can use your DDR2-1066 memory modules for over clocking your Intel CPU: even if your motherboard recognizes it as DDR2-800, you will have memory modules that are guaranteed to run up to 1,066 MHz
Even though the reviewed modules have official timings of 5-5-5-15-T2, you can lower these timings in order to achieve a higher performance – if your motherboard provides this option, of course. According to Corsair, you should be able to run these modules at 4-4-4-4-T1 if your run them at 800 MHz and even 4-4-4-12-T2 up to 1,080 MHz
The memory chips used are from Micron, D9GMH to be more exact – Micron’s full part number for these chips is MT47H64M8B6:D, where “D†is the revision code. The funny thing is that officially these chips are rated DDR2-667, so Corsair handpicks the chips they buy from Micron to see which ones can run at 1,066 MHz or above.
This huge price difference crushes the idea of having average Joe installing this memory kit on their new Core 2 Duo system: as the performance difference between using DDR2-800 and DDR2-1066 was only between 5% and 6% in Quake 4 (you may have a higher performance gain in other games, though), we don’t think paying twice to have such performance gain makes any sense at all – unless you are Richie Rich or a relative of his, of course.
We have a couple of tips for you if decide buying this memory. If you leave the memory configuration on “auto†on the motherboard setup, your motherboard may recognize the modules as DDR2-800 even if it supports DDR2-1066. Also, you can achieve a better performance lowering the memory timings, so we’d suggest you to change the memory timings from “auto†to “manual†and configuring them as 4-4-4-12-T2 instead of the default configuration for a higher performance.
