CompuStocx CSXO XAC-1200 Diablo 2x 1GB PC2-9600/DDR2-1200 Memory Review

Let us begin with the most important part of the test report, because the optical characteristic and packing is of course rather secondary and the highest possible stable performance is the most important factor. CPU on different frequencies depending on the reference clock for the different memory benchmarks. Furthermore the memory modules were tested on another reference board to test the high frequency with higher voltages. The multiplier adjustment remains on 9x with all frequencies, because an adjustment for the CPU in half multiplier steps would be too inaccurate to get nearly the same CPU frequency for all tests.

Microsoft Windows XP Professional SP2 is used as the operating system. The stability was examined with the software Memtest86
and SiSoft Sandra Lite 2007.SP1 program is used for all benchmarks, since it offers extensive adjustments and a fast result comparison. BTW. the latest SiSoft Sandra 2008 version is available on our download server and can be downloaded much faster – ALL benchmarks are also included in the free Lite version.

First the maximum possible frequency of the memory module was determined. The memory frequency was increased in small steps with a fixed memory timing of 4-4-4-10 2T and default memory voltage, as long as the detailed memory test with Memtest86 runs without any errors. This quite long testing time ensured that this frequency works really stable with these modules.

The highest possible frequency with 4-4-4-10 (Tcl Trcd Tras Trp) timings was stable with enormously high 469 MHz.

It’s possible to run much higher frequencies with increased voltages or lower timings, because the frequency values and timings depends directly from each other. Officially CompuStocx specify a memory voltage of 1.80 to 2.40 Volt without loosing the warranty. 2.40 Volt is supported on some motherboards, so the maximum manufacturer frequency of 1200 MHz (600 MHz x2) on CL5 is not possible on all mainboards. It’s necessary to have 2.40 Volt (instead of 1.80 Volt!) to reach DDR2-1200 performance. For this test additionally a slightly modified reference board (Foxconn C51XEM2AA) was used. This reference board supports up to 2.50 V Vmem and this offers a performance of much more than 600 MHz (DDR2-1200).

The highest possible frequency with default DDR2 voltage was compared with two settings. On the one hand 469 MHz with SPD values (these are programmed in the SPD IC by the manufacturer), and on the other hand 200 MHz (x2) with SPD values.

By the way, the “Memory Bus Range” is no benchmark value, but this value is quite simple to calculate by the frequency and is useful for the benchmark comparison.

Here’re the benchmark results:

Frequency Timing RAM Range Int Buff’d iSSE2 Memory bus range
469 MHz fix (4-4-4-10 2T) 6560 MB/s 15008 MB/s
469 MHz SPD (5-5-5-16 2T) 6500 MB/s 15008 MB/s
200 MHz SPD (4-3-3-8 2T) 4724 MB/s 6432 MB/s

Here’s a diagram of the benchmark values:

Here is a direct benchmark result comparison of some DDR2 and DDR memory modules:

The result of the CompuStocx CSX XAC-1200 Diablo is currently (11/2007) on position 2 of all tested RAM kits!

In view of the enormously performance in the upper segment, this is a awesome result. And with the manufacturer release of voltages up to 2.40 Volt, the top position is inofficially exceeded. The benchmark comparison is officially only done with default voltage which is supported on all motherbaords. Everyone who like to get a higher frequency or latency, need the often mentioned higher Vmem.