This article continues the series of reviews devoted to choosing the right overclocking friendly memory kit for systems built around the promising Intel Core 2 Duo processors. In our previous articles we have already discussed in detail fast and expensive PC2-8000 memory (for details see our article called DDR2 SDRAM to Hit 1.1GHz: Corsair Dominator vs. OCZ PC2-8800 Gold Edition) as well as even faster one (for details see our article called Choosing the Right Memory for Core 2 Duo Platform - Part 2: DDR2-1000, DDR2-1067 SDRAM). Today we feel it is time to pay due attention to less supreme but still very interesting DDR2-800 SDRAM.
First of all I would like to stress that in most cases you should consider DDR2-800 SDRAM to be the best choice for Core 2 Duo based platforms. As we have already demonstrated in this article, the overclocked system can reach its highest performance level in case the processor bus and the memory bus are clocked synchronously. And keeping in mind that the typical Conroe overclocking usually occurs at about 400MHz FSB frequency, then the overclocker's DDR2-800 SDRAM can be recommended as the best choice for most enthusiasts. Especially, since most PC2-6400 memory modules have proven capable not only to work at 800MHz with pretty aggressive timing settings, but also to be overclocked to hit much higher speeds at slightly longer latencies.
Of course, we shouldn't disregard the efficiency of fast memory modules for overclocker systems, especially after we have described their universality in our previous materials. As our tests revealed, faster overclocker memory modules designed to run at 1GHz+ frequency can work at 800MHz with pretty aggressive timings. However, the price point is yet another important factor that cannot be omitted here. PC2-6400 SDRAM modules are much more affordable than 1GHz or faster memory solutions. Therefore, these memory modules enjoy most popularity among overclockers.
I have to say that high efficiency of synchronous clocking of the processor and memory busses is not the only argument in favor of mainstream overclocker's memory solutions. Our tests showed that far not all LGA775 mainboards compatible with Core 2 Duo processors can ensure stable functioning of the memory at 1GHz or higher speeds. For example some i975X based mainboards, namely the popular overclocker's product -ASUS P5W DH Deluxe, experience certain problems. As a result, PC2-8000 and faster memory can only be really used to the advantage in Intel P965 based platforms, which limits the application field for this memory quite noticeably.
By the way, this is one of the reasons why we selected ASUS P5B Deluxe mainboard as a test platform for our DDR2 SDRAM test for Core 2 Duo, because this newer Intel chipset is better optimized for work with the high-speed DDR2 SDRAM. At the same time I would like to point out that DDR2 memory usually overclocks even better in Socket AM2 systems. However, for the reasons mentioned in the previous articles of the series, today we are going to look at DDR2 SDRAM performance and operation only in systems with Core 2 Duo processor.
At this point I would only like to add that the memory controller of the new Intel P965 chipset boasts a few features distinguishing it from the predecessors and competitors. The engineers did their best to make this memory controller as intellectual as possible: for the first time it features out-of-order commands execution algorithms that allow more efficient use of open memory pages. As a result, it helps to utilize the DDR2 SDRAM memory bus gets more effectively and reduce the latencies during data processing. So, the iP965 memory controller boasts very different features unlike similar units built into other processors and chips.
However, let's not veer too far away from the main goal of our today's test session. As we have already mentioned we will be looking at 2GB PC2-6400 SDRAM overclocker's memory kits. All the tests will be conducted in the following test platform:
- Intel Core 2 Extreme X6800 CPU (LGA775, 2.93GHz, 4MB L2);
- ASUS P5B Deluxe mainboard (LGA775, Intel P965 Express);
- PowerColor X1900 XTX 512MB graphics card (PCI-E x16);
- Maxtor MaXLine III 250GB HDD (SATA150);
- Microsoft Windows XP SP2 with DirectX 9.0c.
We used our standard set of benchmarking tools for memory stability testing: Memtest86, S&M and prime95. The memory performance was analyzed at the modules nominal voltage as set by the DDR2 SDRAM manufacturer.