PDC22G9200ELK is a PC2-9200 2 GB memory kit from Patriot, meaning that it can be run up to 1,150 MHz maintaining its programmed timings (5-5-5-12), being targeted to serious overclockers. We reviewed this kit and we will see if this kit is really capable of running at 1,150 MHz and what are the advantages of using PC2-9200/DDR2-1150 memories over regular ones.
A lot of people think that the memory modules will always work at their labeled clock rate. This isn’t true. Who decides what speed your memories will run will be your motherboard (in the case of Intel processors) or your CPU (in the case of AMD processors). If you replace your DDR2-533 memories with DDR2-800 ones it is not guaranteed that your new memories will be running at 800 MHz. Sometimes, due to misconfiguration, they will still be running at 533 MHz (you need to enter the motherboard setup and set the new memory clock rate). In other cases, you may be using an old motherboard that only recognize up to DDR2-667 and your DDR2-800 memories will be running at 667 MHz, not 800 MHz. AMD processors use a funny clock division scheme where your memory may be running at a lower clock rate (for example, with Athlon 64 X2 5000+ DDR2-800 memories work at 742 MHz – click here for a detailed explanation on this issue).
A good way to check the real clock rate your memory modules are using is by running a program called CPU-Z, and clicking on the Memory tab.
So, why we are telling you all this? Because if you buy this memory module from Patriot thinking that it will automatically work at 1,150 MHz you are wrong. If you didn’t set any overclocking on your PC it will work at 800 MHz (or a little bit less, if you have an AMD processor) or at 1,066 MHz, if you have an Intel processor and your motherboard is capable of setting your DDR2 clock at 1,066 MHz (for example, on motherboards based on Intel P965 and nForce 680i chipsets). In this case you need to enter the motherboard setup and configure the memory at 1,066 MHz or it will work at 800 MHz.
Then what is the use of DDR2-1150 memory modules? Overclocking. If you are not into overclocking, this memory isn’t for you.
If you do overclock, then this memory module may be a terrific product for you to expand your computer’s overclocking capability.
Let us explain this further. On the majority of motherboards available on the market there is no separated clock generator for the memory modules, so the clock generator used by the CPU will be also used by the memory (one good exception are the motherboards based on nForce 680i chipset, where there is a separated clock generator for the memories).
Overclocking is done by increasing the CPU external clock rate and since the memory clock rate is tied to the CPU external clock, you will automatically overclock your memory as well when you overclock your processor.
Let’s give you a real example. Let’s say we have a Core 2 Duo CPU with an external clock rate of 1,066 MHz. The real external clock rate of this processor is of 266 MHz. As Intel CPUs transfer four data per clock cycle they are rated as having an external clock rate four times higher than the real clock rate that is being used. Let’s also say that we have two DDR2-800 memory modules running at 800 MHz. The real clock rate of these modules is of 400 MHz. Since DDR2 and DDR memories transfer two data per clock cycle, they are labeled as if their clock rates were two times higher than their real clock rate.
On a motherboard using a single clock generator (the majority of boards found on the market) the 400 MHz memory clock rate will be generated by multiplying the CPU external clock rate by 1,5 x (this is also referred as 3:2 ratio).
So what happens with your memory when you overclock your CPU external clock rate from 266 MHz to 290 MHz? They will be working at 435 MHz (870 MHz). So they will also be overclocked.
Let’s say that increasing your CPU external clock rate above 290 MHz your system was unstable, so you came to the conclusion that this is the maximum clock rate your computer can achieve.
However, one question is still on the air: what was limiting your system from going beyond 290 MHz? Was the CPU? Or was the memory?
By replacing your DDR2-800 memories with a higher-grade memory you will be able to check this out. For instance, if by installing DDR2-1066 memories – where the manufacturer guarantees that the memory can work up to 1,066 MHz – your system works fine when increasing your CPU external bus over 290 MHz, it means that your DDR2-800 memory was the limiting factor for achieving a higher overclocking. However, if you are not able to push the clock rate above 290 MHz this means that another component is limiting your overclocking (maybe the CPU itself).
These memory modules from Patriot are guaranteed to work at 1,150 MHz, so you may be able to achieve higher overclocking with your CPU in the cases where the memory is the limiting factor.
Of course when working at a higher clock rate the memory is capable of delivering a higher transfer rate, but the main goal of using these memories is allowing you to achieve a higher CPU overclocking – the extra memory performance will be a consequence.
[nextpage title=”Patriot PDC22G9200ELK Memory Kit”]
In Figure 1, you can see the package for this PC2-9200 2 GB memory kit and in Figure 2 the two DDR2-1150 1 GB memory modules. Patriot also offers this kit with 1 GB version, using two 512 MB modules.
Patriot guarantees that these memory modules can run up to 1,150 MHz maintaining 5-5-5-12 timings, which is ok for this clock grade, as these are the same timings used by DDR2-1066 modules we’ve seen from Corsair and Patriot.
These modules use the famous D-revision Micron chips. There are several different versions of this chip around, and the one used on these modules is D9GKX. The part number for this memory chip is MT47H64M8B6-25E and it is officially rated as DDR2-800. Patriot could label them as DDR2-1150 through a process of testing: some chips from a batch can work fine above their specs, so it is just a matter of selecting the chips that can work fine at 1,150 MHz. Inside a batch there may be not so many chips that can work at this clock rate, so that is why Patriot has to charge more for these memory modules.
Since each chip can store 512 Mbits of information, 16 chips are used on an 1 GB memory module (512 Mbits x 16 / 8 = 1 GB).
[nextpage title=”Main Specifications”]
Patriot PDC22G9200ELK memory kit main features are:
- Total capacity: 2 GB (2x 1 GB modules)
- Speed: DDR2-1150/PC2-9200
- Programmed Timings: 5-5-5-12
- Recommended Voltage: 2.3 V
- Memory chips used: Micron D9GKX (MT47H64M8B6-25E)
- Warranty: Lifetime
- More information: https://www.patriotmem.com
- Average Price in the US*: USD 300
* Researched at Shopping.com on the day we published this review.
[nextpage title=”Our Tests”]
We had two goals with our review: first, to see if this memory kit could really run at 1,150 MHz. Second, to see the maximum clock rate we could put this kit to work keeping its labeled timings (5-5-5-12).
Of course when working at a higher clock rate the memory is capable of delivering a higher transfer rate, as the transfer rate is directly proportional to the clock used (transfer rate = number of bits x clock rate / 8). In our review, however, we were not interested in learning what is the maximum transfer rate achieved by these memory modules, since this memory kit is targeted to people that want to achieve a higher clock rate with their CPUs – a higher transfer rate is a consequence.
For our review we used an nForce 680i-based motherboard (ECS PN2 SLI2+) and a Core 2 Duo E6700 CPU. This motherboard has a separated clock generator for the memory, so we could increase the memory clock without increasing the CPU clock, which is terrific to evaluate this kind of memory – since the CPU won’t be overclocked only the memory modules will limit the maximum clock rate we will achieve.
We could set this kit to run at 1,150 MHz with their nominal 5-5-5-12 timings without sweat. So they deliver what the manufacturer is saying they are capable of.
Then we decided to see what was the maximum clock rate these memories could run maintaining their 5-5-5-12 timings (if you increase timings usually you can achieve higher clock rates but lowering memory performance) and voltage (2.3 V). We could set them up to 1,219 MHz (609.5 MHz x2) as you can see in Figure 5 (on setup the memory clock was set as 1,244 MHz, but let’s consider the clock as read by CPU-Z), 153 MHz more than their nominal rating.
We could set them above 1,244 MHz but the system didn’t pass our stability test. So we decided to increase the memory voltage to 2.4 V to see what happened and with this new voltage we were able to put the memories running at 1,280 MHz (640 MHz x 2) as you can see in Figure 6. This is 214 MHz over DDR2-1066 standard clock rate.
An important thing we discovered during our tests is that you have to set the memory voltage manually at the motherboard setup or you won’t achieve the full potential of this product. We forgot to set this voltage and the maximum clock rate we could achieve was 1,150 MHz, as the system fed the memories with 1.85 V instead of 2.3 V.
Patriot PDC22G9200ELK 2 GB memory kit delivers what the manufacturer promises: it is a true DDR2-1150/PC2-9200 2 GB memory kit, being perfect for overclockers that want to achieve a higher overclocking level with their systems and their current DDR2-800 or DDR2-1066 is the current bottleneck.
Even though it is officially rated only 86 MHz above 1,066 MHz, on our tests we could put it working at 1,219 MHz maintaining its default voltage (2.3 V), so we are talking about 153 MHz above DDR2-1066. Increasing voltage to 2.4 V we were able to put this kit running at 1,280 MHz, or 219 MHz above 1,066 MHz.
Of course this kit is targeted only to the ultimate overclocker. Regular users won’t have any benefit from using this kit (as it is targeted to overclocking) and even overclockers have to think if it is worth paying a lot more to get some more megahertz.
The problem with this kit is its price. It costs around USD 300 while a 2 GB DDR2-1066/PC2-8500 kit from the same manufacturer (PDC22G8500ELK model) costs only USD 190 and Newegg.com offers a USD 40 rebate, making this product a far better option for the average overclocker, costing exactly half the price. Updated 05/24/2007: Newegg.com lowered the price for this memory kit a little bit and is now also giving a USD 40 mail-in rebate for the reviewed memory kit, so the final price at this store is now USD 256, making it much more affordable.
Of course we know that die-hard overclockers with deep pockets don’t mind paying extra to achieve the highest overclocking possible to impress their friends.