Mushkin XP2-6400 2GB Kit (2x1024MB) PC2-6400/DDR2-800 Memory Review


The introduction ...

Mushkin's current XP2-6400 DDR2-800 memory is not only highly overclockable, but also reasonably priced.
The high performance of the DDR2 800 modules exceeds the expectations and the reason becomes clear with a look
under the heatspreader. Because Mushkin uses the well-known Micron D9GMH memory chips on the tested modules and
these memory chips are also used on high-end DDR2-1200 modules.
Just the maximum allowed memory voltage for the Mushkin XP2-6400 RAM is a little bit lower with 1.9 Volt up to 2.1 Volt.
But of course, it's well-known that overclocking isn't always within the specifications.
The following review will show you all details about this 2GB kit and give you an extensive comparison to all memory modules
tested so far.




Thanks for the support ...

Many thanks for the support with the XP2-6400 (1x996523 or 2x991523) 2GB PC2 6400 / DDR2 800 CL4 kit by Mushkin.

The 2 GB kit contains 2x 1024 MB 240-pin DIMM DDR2-800 (PC2-6400) memory modules and has a price of
approx. 160 Euro (11/2007).
They're available in the Mushkin Web Store and at our sponsors.



The supply of the two 1024MB PC2-6400 memory modules ...

The two very well protected memory modules are delivered in this packing:



That is contained in the scope of delivery ...

Mushkin supplies the two memory modules as well as an troubleshooting guide and installation guide on the backside
of the packing, which should make it possible for less experienced users to install them easily.

Here is a picture of the two contained XP2-6400 memory modules:



The technical data ...

Manufacturer Mushkin
Article number 1x 996523 or 2x 991523
Memory 2GB kit (1024MBx2)
Package 240-pin DIMM
Type DDR2 PC2-6400
Configuration 128Meg x 64
Error correction NON-ECC
Speed DDR2 800 (400 MHz * 2)
Voltage 1.90 - 2.10 Volt
Memory timing 4-4-3-10 (Tcl-Trcd-Tras-Trp)



Characteristics and other features ...

The memory modules are provided on a green plate with black passive heatsinks (heatspreader) to get lower temperatures,
also with higher frequencies and/or higher voltages.
This is especially important with these Mushkin modules, because a high voltage and/or frequency could destroy the
DDR2 RAM without a good cooling.
The heatspreader is pressed very evenly to the thermal pads of the memory chips and offers a good heat dissipation.
Furthermore the test modules comes with EPP (Enhanced Performance Profiles) to get reduced latencies and high frequencies
on latest generation motherboards with EPP support.



Benchmark values and test results ...

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.
The test results are based on an ASRock AM2XLI eSATA2 SLI motherboard with an Athlon 64 Socket AM2 3000+
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 455 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 Mushkin specify a memory voltage of 1.90 to 2.10 Volt without loosing the warranty.
In view of the standard DDR2 memory voltage of 1.8 Volt one can obtain considerable results with 2.10 Volt,
whereby it was possible in the test with 2.1V to get far above the 500 MHz hurdle.
This isn't possible on all motherboards, because on the one hand it is necessary that these high clock rates are supported
by the motherboard and on the other hand it's absolutely necessary to support this high memory voltage (Vmem) of approx. 2.0V - 2.1V. For this test additionally a slightly modified reference board (Foxconn C51XEM2AA) was used.
Results of 600 MHz and above would come true with these Micron D9GMH memory chips on approx. 2.20 - 2.40 Volt.
However, Mushkin doesn't allow these voltages above 2.10 Volt officially, so you'll loose the warranty.

The highest possible frequency with default DDR2 voltage was compared with two settings.
On the one hand 455 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:

RAM Range Int Buff'd iSSE2
Memory bus range
455 MHz
fix (4-4-4-10 2T)
6350 MB/s
14560 MB/s
455 MHz
SPD (5-5-5-15 2T)
6264 MB/s
14560 MB/s
200 MHz
SPD (4-3-3-8 2T)
4608 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 Mushkin XP2-6400 modules with standard voltage was 4 MHz over the higher priced Mushkin XP2-8500 kit
and shows, how close the results are in the upper range.
As already often mentioned, the voltage of the memory modules is enormously important and that is also the difference
to much more expensive high-end modules. These were tested with higher voltages and get the manufacturer approval for
this voltage, frequency and latency.
However, everyone can decide to overclock above manufacturers specification on their own risk in order to get much more
performance for less money.


Result and general impression ...

The Mushkin 2GB XP2-6400 kit exceeds the expectations, because the result on the same memory voltage is a little bit
better than Mushkin's XP2-8500 modules.
Thanks to the Micron D9GMH chips used on the XP2-6400 test modules this 2 GB DDR2 kit reaches nearly the top of all
still tested memory modules.
The even contact pressure of the heatspreaders provides a good cooling and allows thereby a very high memory voltage,
which is currently absolutely necessary for higher frequencies beyond the PC2-6400 standard.
But also with the standard DDR2 voltage of 1.80 Volt these modules would be glad to run on a fast motherboard with high memory timings.
All in all the Mushkin 2GB XP2-6400 kit is thus a good investment in great performance !



Read on in the hardware test area with several hardware reviews ...


All pictures and article copyright 2007