Kingmax Mars DDR2-667 KLCC28F-A8EB5

Performance:

Due to some fairly impressive overclocks we've been experiencing on an ASUS P5LD2 Deluxe motherboard, which sports Intel's i945P Chipset thus supporting 1066/800MHz FSB processors. Due to some thermal and overclocking concerns, we won't be using an Intel Pentium D today but rather a retail Pentium 4 530 (3.0GHz) which has proved repeatedly to be a phenomenal overclocker. Without further ado, here's the system setup used in testing:

Although the P5LD2 Deluxe features the ASUS Stack Cool 2 Technology, which is a fan-less cooling solution for the PCB, and this system was running in open-air on a bench we continued to use multiple 120mm fans for assisting in cooling. At the top of the motherboard was a 120mm fan pointed toward the Ultra Product's LGA-775 CPU cooler while next to the memory slots were two additional 120mm fans. With an open-air system and multiple 120mm fans, it's about the best you can get without breaking out the water cooling system. Another important system note is due to an American Megatrends Inc (AMI) BIOS and NVIDIA Linux driver issue with Fedora, which causes X to fail on load, we turned to the good guys over at Ubuntu. For benchmarking, outside of the memory testing in memtest86+, we used the recently released Ubuntu 5.10 (Breezy Badger) Colony 3 development release.

Once the 2 x 512MB of Kingmax KLCC28F-A8EB5 DDR2 memory was installed, we proceeded to enter the ASUS P5LD2 Deluxe 0312 BIOS, which is the latest official release at the time of publication. When entering the Advanced Chipset settings page, and manually looking at the SPD timings for the memory, we found them to be timed at 5-5-5-15, and these stock SPD timings were confirmed by running Memtest86+ v1.60, and also looking at the Kingmax datasheet. For this initial testing, all overclocking, timing, and voltage settings were left stock. To find out how tight we could squeeze the memory timings on the Kingmax modules with Elpida E5108AE-6E-E chips at DDR2-667 speeds, we proceeded to properly tighten the timings and increase the voltages when needed. After tweaking for quite some time, we managed to run the modules stable at 3-3-3-8! When attempting to run the memory any tighter, with our voltages already maxed, the system would fail to properly boot. We felt these timings were most impressive compared to the stock 5-5-5-15 especially as we had no prior experience with these specific Elpida chips. Also, Corsair's 5400UL runs at a 3-3-2-8 latency. Now that we knew how tight the Kingmax memory could run at DDR2-667, our next objective was to see how far we could push the memory frequency. To properly do so we loosened the timings back to their SPD of 5-5-5-15 and then began increasing the FSB and memory voltage respectively. After several setbacks, we ended up maxing the Kingmax KLCC28F-A8EB5 at DDR2-850MHz requiring 2.3V for the memory and a FSB of 255MHz, which resulted in the processor running at 3.825GHz (255 x 15). We had attempted to run the memory at 5-4-4-15 with 2.1V and 2.2V, while clocked at these frequencies, but half-way through Memtest86+ v1.60 resulted in a countless number of errors so we were forced to return to 5-5-5-15 and bumping the voltage to the maximum of 2.3V; after making several other attempts to correct the situation. Although we couldn't break the 1000MHz barrier, like the Corsair XMS2 PC2-5400UL is generally able to do, we were however fairly impressed by the memory's ability to run at 850MHz while at the SPD timings and keeping in mind we were on air-cooling, which hindered the CPU clock speed.

Thus the various scenarios we'll be benchmarking with the Kingmax are:

· 200MHz FSB (3.00GHz) - DDR2-667MHz - 5-5-5-15 - 1.80V (memory)
· 200MHz FSB (3.00GHz) - DDR2-667MHz - 3-3-3-8 - 2.30V (memory)
· 255MHz FSB (3.82GHz) - DDR2-850MHz - 5-5-5-15 - 2.30V (memory)
· CORSAIR XMS2 PC2-5400UL: 200MHz FSB (3.00GHz) - DDR2-667MHz- 3-3-2-8 - 2.10V (memory)

For comparison purposes today, we'll be using Corsair's popular 2 x 512MB PC2-5400UL that uses Micron's D9 ICs. Even though Corsair guarantees the memory can run at 3-3-2-8 with a memory voltage of 2.1V, their SPD programmed values are 4-4-4-12 so a quick adjustment in the BIOS is needed to obtain these times.