Of course you can use your DDR2-1066 memory modules for overclocking 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.īut, just like AMD CPUs, if you don’t plan overclocking your Intel CPU and your motherboard doesn’t support DDR2-1066 but you want to have the fastest memory available, we’d recommend you to pick a low latency DDR2-800 memory, like the abovementioned TWIN2X2048-6400C3 kit from Corsair. On almost all socket LGA775 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. The problem, however, is that only very few socket LGA775 motherboards accept DDR2-1066. 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. For the regular user that wants to achieve the maximum system performance but without overclocking there are better solutions on the market for this platform, i.e., DDR2-800 memories with lower latencies –TWIN2X2048-6400C3 also from Corsair is a good example, as it is a DDR2-800/PC2-6400 kit where the memory runs with C元 instead of CL5.įor the regular user that does not overclock 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. On AMD side, as socket AM2 CPUs only support up to DDR2-800, these memories can only be used for overclocking, so there is no point of buying these modules for a socket AM2 CPU if you are not going to overclock it.
The main problem with DDR2-1066 memories today is compatibility, as only a few motherboards are able to use them to their full potential. Let’s see how the 2 GB kit performs.įigure 1: Corsair TWIN2X2048-8500C5 2 GB DDR2-1066/PC2-8500 memory kit. 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. These models are not only targeted to both Intel and AMD overclockers 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. 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. nVidia SPP's (northbridge) can handle a much larger voltage than can Intel chipsets such as your P35.With the introduction of AM2 socket by AMD all new high-end PCs are finally using DDR2 memories. The JEDEC specification you listed (2.3v), is primarily the province of modules tailored for nVidia chipsets, some are rated at 2.3 -2.35v.(the latter figure is EVP (Extended Voltage Protection)- basically a "do not exceed" threshhold). If the modules need more than that then a commensurate voltage bump for the MCH (northbridge) is also usually needed, which if left to "Auto" settings usually means a lot more voltage than is required, which in turn generates a lot of heat that the chipset heatsink needs to dissipate. Remember that the JEDEC specification for DDR2 is 800 -anything higher than that, whether it's the manufacturer (XMP, EPP) or user's profiles is overclocked by definition.Īs for om personal experience anything over 0.1v over the particular modules' specification* is russian roulette. Running at a higher bandwidth is realistically the realm of CL4 (ideally 4-4-4-12) binned modules. Mix and match RAM is probably not the best approach for OC'ing, so I'd leave the memory divider at 1:1 (DDR2-825), especially since the RAM you have (at least the lowest specced part) is CL5 which implies that it is low-binned (budget).
412 FSB shouldn't be much of an ask for a Q8400, and should be do-able on stock Vcore.