Intel P35 Memory Performance: A Closer Look

Memory Test Configuration

In the original DDR3 vs. DDR2 review a 4MB cache E6420 was overclocked to provide 8x333 2.66GHz testing. An X6800 was used to provide the 10x266 2.66GHz configuration for comparison. For the revised tests, we used the X6800 for all testing since it was simpler to use an unlocked CPU with the flexibility to run all of the CPU configurations needed in our benchmarking. In addition we have seen some variation in the performance of different Core 2 Duo processors and we wanted to remove that variable. While we don't know exactly why, X6800 processors are often a bit faster in gaming benchmarks than some other Core 2 Duo chips. We suspected this might be distorting the real improvement in our gaming test and using the same processor removes that variable.

Memory is now also limited to Corsair DDR3 and DDR2 since there were minor variations in the performance of our two DDR3 memories. This eliminates another potential variable from the benchmarks. All other components are the same as the initial review.

Memory Performance Test Configuration
Processor	Intel Core 2 Duo X6800 (x2, 2.93GHz unlocked, 4MB Unified Cache) 10x266 - 2.66 GHz 8x333 - 2.66GHz
RAM	Corsair CM3X1024-1066C7 (2GB Kit - 2x1GB) Corsair Dominator CM2X1024-8888C4 (2GB Kit - 2x1GB)
Hard Drive	Samsung 250GB SATA2 enabled (8MB Buffer)
System Platform Drivers	Intel - 8.3.0.1013
Video Card	Leadtek WinFast 7950GT 256MB
Video Drivers	NVIDIA 93.71
CPU Cooling	Intel Retail HSF
Power Supply	Corsair HX620W
Motherboards	Asus P5K3 Deluxe (Intel P35 DDR3) Asus P5K Deluxe (Intel P35 DDR2) Asus P5B Deluxe (Intel P965 DDR2)
Operating System	Windows XP Professional SP2
Bench Software	SiSoft Sandra XI SP2 CPU-Z 1.40 Everest 4.0 Super Pi 1.5 Far Cry - River Demo

Benchmarks with the P965 at 1333 FSB were not really of much use in our testing, since the memory ratios would not also allow standard memory speeds of 800 and 1066 when the bus was set to 1333. Also none of the DDR2 memory we had would run at 1333 on the P965. The P965 Is not really designed for a stock 1333 FSB so it was only tested at a 1066 FSB.

Since the P965 was not well suited for 1333 testing, the P35 was adjusted down to 1066FSB for comparison of memory performance. With that setting performance could be tested at DDR2-800 and DDR2-1066. However, a 1333 memory ratio cannot be selected with a 1066 FSB on the P35 boards that were tested, so it was not possible to run memory at 1333 and the CPU at 1066. That is the reason there are no 1333 memory speeds reported under the 10x266 CPU timings.