screenshot below indicates memory's behavior under the SPD command at default (200FSB 1:1) speed.
As Kingston specified we see above a CAS Latency of 2.5-3-3-6, at 200Mhz (200FSB 1:1) or DDR400. In the our next CPU-Z screenshot below the CAS-latencies are raised to CL3-4-4-8 under the SPD command, at 250MHz (250FSB 1:1) or DDR500.
The aspect ratio will remain at 1:1 for all our tests, and the DDR-voltage (VDIMM) will remain at 2.75V, increasing to 2.85V only at 250FSB (DDR500). For our first set of benchmarks I employed SiSoftware's Sandra Professional memory module, in both buffered and un-buffered modes. Since testing on Intel's Canterwood/Springdale platforms, I've found there's a significant improvement in performance, whenever the SPD (Serial Presence Detect) command is enabled over Manual settings. Fortunately the average PC-user will have a minimum of BIOS adjustments to concern himself/herself with. As indicated above by CPU-Z, our KHX3200K2/2G ran at CL2.5-3-3-6 at the default speed of 200MHz, or DDR400. Anything above this, and SPD automatically raised the CAS-latency to CL3-4-4-8. I did try running the memory at a tighter CL2 by increasing DDR-voltage, however; I wasn't able to reduce latencies. I was, however; very impressed the memory ran as fast as 250MHz or DDR500 attaining PC4000 performance given the kit size.
As this particular memory doesn't fall into the recent genre of “Xtreme Series” kits designed to run from DDR400 to DDR500, such as Corsair's Twin-X1024 3200XLPRO reviewed here
The bandwidth is certainly impressive given the memory's default latency setting. There are a few variables which will inevitably affect bandwidth during these tests, including the prima facie enhancements, such as running PAT in Turbo mode, therefore I've left this setting on Standard. The memory performed completely stable through 250FSB, at least through Sandra's memory benchmarks. Our next series of benchmarks feature Aida32 system benchmark. Specifically it's READ and WRITE measurements. Aida32 usually produces much higher results then SiSoftware's Sandra Memory module.
Another benchmark utility, which memory will effect, is PiFast. For our purposes I chose Hexus Pifast Challenge as it is most likely the largest database of its kind for comparative results. Those whom participate, usually provide a detailed description of their system, I find the information invaluable. I included screenshots of results from default speed, and the highest stable overclocked speed, at 200FSB, and 250FSB respectively.
Certainly there's a significant difference in the Calculation of Pi at higher frequencies, and CPU speed is as important to this benchmark as memory commands. To run this benchmark yourself simply follow this link Hexus PiFast Challenge. Our next graph exemplifies FutureMark 3DMark03, and 3DMark2001SE benchmark results from each representing 200FSB to 250FSB system speeds. I ran the memory ran under SPD command, with PAT in Standard mode. VDIMM began at 2.65V from 400MHz (DDR) to 2.85V at 500MHz (DDR). CAS-latencies under the SPD command ran from 2.5-3-3-6 at DDR400 to 3-4-4-8 at DDR500.