DDR has been around now for a good number of years and since its birth I started hearing people ask when is DDR2 going to be out? DDR2 has finally emerged and will eventually take over current DDR like SDRAM was taken over by DDR a few years back. Currently there are only a small number of Intel motherboards and no AMD motherboards that can use DDR2. This fact leaves users with the question of should I upgrade or wait a while?
What are the major differences between DDR1 and DDR2?
Current DDR uses a 2-bit prefetch while DDR2 implements a 4-bit prefetch, prefetching is gathering data before it is needed. This basically means that every bus cycle 4 bits of data will be transmitted instead of 2. Of course this probably leads you to wondering why the overall bandwidth isn’t doubled as well. The simplest answer I can give is because information is only requested half as often. DDR2 also utilizes a FBGA (Fine Ball Grid Array) while DDR uses a TSOP-II (Thin Small-Outline Package). The FBGA uses a find pitch ball arrangement on the underside of the package, where the TSOP has leads protruding from the sides of the package. Because the contact point of the FBGA is on the bottom of the package, the package can be made smaller than the TSOP.
New Features
There are also a few new features for DDR 2 that are good improvements over current DDR. With original DDR excess signal noise is eliminated using terminating resistors that are built into the motherboard. In DDR2, resistors are still used eliminate the excess noise, however these resistors are built into each of the memory chips on the module which keeps them closer to the source of the noise. This is intended to reduce interference within the chip.
Posted CAS and additive latency are two new technologies that work together to prevent data collisions within the memory as well as better utilizing the data transferring more read/write within each clock cycle. Off-chip driver calibration (OCD) is another new technology which provides the option of tightening the variance of the pull-up and pull-down output driver at 18 ohms nominal. This increases the signal integrity and the system timing margin. The table below is a summary of the major differences between DDR and DDR2.
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DDR
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DDR2
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Data Bus
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64 bits
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64 bits
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Data Rate
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200/266/333/400 Mbps
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400/533/667 Mbps
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Bus Frequency
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100/133/166/200 MHz
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200/266/333 MHz
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DRAM Frequency
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100/133/166/200 MHz
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100/133/166 MHz
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Package Type
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TSOP-II
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FGBA
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Densities
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256 MB, 512 MB, 1 GB
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256 MB, 512 MB, 1 GB
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Voltage
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2.5 volts
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1.8 volts
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Prefetch Size
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2 bit
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4 bit
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Burst Length
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2/4/8
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4/8
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CAS Latency
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1.5, 2, 2.5
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3+, 4, 5
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Write Latency
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1T
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Read Latency-1
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Packaging
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TSOP (II), TBGA
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FBGA
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The TWIN2X1024-5400C4PRO is a 1024 MByte matched pair of 240-pin DDR2 SDRAM DIMMs. This memory has been verified to operate at 675MHz at the low latencies of 4-4-4-12 with 1.9v. Each module pair is tested together in an Intel-based motherboard at 675MHz and packaged together upon completion.
The front and back of the modules are basically identical; the only difference is the specification sticker on one side. This DDR2 has platinum heat spreaders with 24 activity LEDs built into them so you can see your memory in action. This feature will be looked at in more detail later in the review.
The memory comes with installation instructions in five languages incase you are unsure on how to install them. You also get a flier about their monthly email newsletter which you can sign up for on the main page of Corsair’s website.
The test systems that will be used are outlined below and are almost identical. The only differences between the two is the memory and motherboards. The Corsair DDR2 will be tested on an Abit AA8-3rd Eye while the original DDR is tested on a Albatron PX915G Pro.
Test systems
Abit AA8-3rd Eye, Intel Pentium 4 2.8GHz LGA775, 1GB (2x512MB) Corsair TWIN2X1024-5400C4PRO (4-4-4-12), Albatron PCX5750 (425/500), 30GB 7200RPM Western Digital hard drive, Windows XP SP1a.
Albatron PX915G Pro, Intel Pentium 4 2.8GHz LGA775, 1GB (2x512MB) Corsair TWINX1024-3200LL DDR400 (2-2-2-5), Albatron PCX5750 (425/500), 30GB 7200RPM Western Digital hard drive, Windows XP SP1a.
Everest Home Edition Memory Benchmark
Everest is a free and good benchmarking tool for memory read/write bandwidth. As you can see there is a difference between regular DDR and DDR2 running at their stock speeds. The difference between the two isn’t extraordinary but it can be seen. With the DDR2 running at its rated speed of 339MHz you can see that there is a huge increase in bandwidth, 7026 MB/s is definitely nothing to scoff at.
SiSoft Sandra Memory Bandwidth Benchmark
This memory benchmark also shows similar resuts to Everest with there being little difference between regular DDR and DDR2. Again however the benefit of DDR2 at 339MHz can easily be seen and appreciated.
SYSmark 2004 Internet Content Creation
The overall score for SYSmark 2004 internet content creation the same at the standard speeds for both the DDR and DDR2. With the DDR2 running at its rated speed of 339MHz there is an clear increase in the overall score.
SYSmark 2004 Office Productivity
With the office productivity section of SYSmark 2004 the regular DDR and DDR2 are identical at their stock speeds. After taking the DDR2 to its rated 339MHz there is an obvious improvement.
RealStorm Benchmark 2004
RealStorm does not test the video card at all which makes which makes it ideal for this kind of testing. All of the options were left at the default except I changed the resolution to 640×480. The original DDR and DDR2 at their standard speeds are very close while the DDR2 at 339MHz pushes way past both of them.
dBpowerAMP
dBpowerAMP is a free music converter which I used to convert a wav to mp3. With the regular DDR and the DDR2 at 266MHz the file was converted in the same amount of time. With the memory at its rated speed of 339MHz it converted the file 6 seconds faster.
Lower is better
Corsair has long been known as one of, if not the best memory for overclocking. I left the timings at 4-4-4-12 and started increasing the FSB while adding more voltage to the CPU, memory, and northbridge as needed. My final result was a FSB of 270 taking my 2.8GHz Pentium 4 to 3784MHz! To achieve this overclock I flashed the BIOS to version 15 and set the DDR voltage to 1.9v, northbridge to 1.65v, and CPU to 1.5875v. I did not lock the PCI-Express bus but did lock the PCI to 33.33MHz. I could tell that the memory had a lot more in it but my processor seemed to be maxed out which is understanding since it was running almost 1000MHz faster than normal. If I increased the FSB any more it simply would not take, even with more voltage to everything. With an unlocked processor this memory could be taken even farther but you will need an engineering sample for that.
| CPU | Memory |
Activity LEDs
I made a short video of the activity LEDs in action so you could get an idea of how they look. I turned down the lights so that the LEDs could be easily seen for the video. In full daylight you are able to clearly see the LEDs but for the video darker was better. The below video is a 1MB Windows Media 9 file so you will need the codec if you don’t already have it. If you are not in a Windows environment I have also encoded the movie in MPEG format for your viewing pleasure. The following file is the same movie but a 5MB MPEG1 version which has been zipped for compression, to download this file click here
Conclusion
Though I have always known Corsair memory to be the very best they have again surpassed my expectations. With DDR2 being fairly new to the market its full potential has yet to be seen. Within the next 6-12 months we should see DDR 2 to start becoming more predominate while DDR is slowly phased out like SDRAM was when DDR was introduced.
Motherboards and chipsets will also continue to improve giving more headroom to quality memory like this which begs to be overclocked. Though there is very little talk at this point for AMD to start using DDR2 it’s only a matter of time. You can see throughout the benchmarking that running both DDR and DDR2 at the processors standard memory speeds there is not a huge difference. However when you really take the memory to where it should be the results are phenomenal.
This memory is going to cost you some cash though, about $400 for 1GB which may be more than some want to swallow. What I really want to stress about this memory though is you will not be disappointed if you are using a good motherboard and processor and want to do some serious overclocking. If you are an average user or something who really isn’t concerned with overclocking I would advise you to stick with Original DDR and wait a while for all the new technologies out there to catch up with each other.
Because I am so impressed with this memory and am going to give it a 10/10 and award it the OCmodshop Seal of Approval. I would like to thank Corsair for making this review possible.
Pros
- DDR2 potential can easily be seen
- Highly overclockable
- Very impressive memory scores
- Heatspreaders with activity LEDs
- Takes over where DDR1 stops
Cons
- None