Overclocking Performance (Highest Ratio at Highest Speed)

With the OCZ PC2-9200 Flex XLC rated at DDR2-1150, you are already at the highest overclock we have tested on DDR2 at the speed rating of the memory. It is noteworthy that The Flex XLC goes even further - to DDR2-1172 - on what is one of the most demanding motherboards for testing DDR2 memory. Performance of the aggressively binned Micron D9 memory chips proves the utility of binning for speed. OCZ Flex XLC is the fastest memory we have tested so far by a wide margin.

The timings required for a top DDR2-1172 were the rated 5-5-5-18 at 2.35V. These are certainly not glamorous timings compared to 3-3-3 at DDR2-800, but the fact remains that memory speed and performance still scaled well to the top speed.

Highest Memory Speed

The NVIDIA nForce 680i motherboard allowed us to climb even higher. OCZ Flex XLC was stable at an unlinked CPU FSB of 1733 and a memory speed of DDR2-1300.


To get the CPU speed close to our stock test speed of 2.93 GHz, we lowered the multiplier to 7 at this 433 base. This yielded a CPU speed of 7x433 or 3.03 GHz. Memory at this speed was a stable DDR2-1300.

Click to enlarge

Comparing test results to those from the ASUS 975X test platform will show you faster results with the ASUS. This is a result of the 3.22GHz speed of the ASUS at the top compared to 3.093GHz top speed on the 680i. If you refer back to the performance charts on page 3 you will find performance numbers at DDR2-1172 at 2.93GHz. Comparing those to the 680i performance results shows performance data in line with the speed expectations.

The OCZ PC2-9200 Flex XLC topped the overclocking chart by a wide margin. Performance was impressive on the P5W-DH at DDR2-1172, but it was even more outstanding on the 680i at DDR2-1300.

Game Performance Comparison Final Words
Comments Locked

29 Comments

View All Comments

  • photoguy99 - Saturday, December 9, 2006 - link

    Thanks for your help Wesley, it's just takes a little time for me to get my head around this stuff.

    Just to clarify, I think I see the answer two #2:

    If you have an unlocked CPU, the only benefit to this memory is a 5-8% performance increase.

    In this case I don't think it matters if you are an extreme overclocker - extreme as you wanna be - this is the only benefit you can ever get with this RAM with an unlocked CPU, no matter what you do.

    If you have the cash, nothing wrong with a small performance bump for $300 extra - I am not judging anyone who buys this, just trying to clarify.

    regards,
    pg

  • photoguy99 - Saturday, December 9, 2006 - link

    apologize for double post, accident...
  • photoguy99 - Saturday, December 9, 2006 - link

    Sorry for being ignorant here, but can someone help break this down:

    1) What % faster is FlexXLC-1150 on real life benchmarks (on average), compared to value DDR2-800, at the same CPU speed?

    2) Do I understand correctly that if you have an unlocked CPU multiplier, then the only benefit to this memory ever is the % improvement from question 1?
  • Wesley Fink - Saturday, December 9, 2006 - link

    The tables on page 4 show performance at the same 2.93GHz from DDR2-400 to DDR2-1172. There are also results on the last line for the top speed on the 975X at stock 11X multiplier - so results can be compared to previous test results. You can see the performance differences in each benchmark in those tables. Performance increases are there as speed increases, but they are extremely small. We also commented several times in the review that those shopping for value per dollar should buy a good value to mid DDR2 memory rated at least DDR2-800.

    Flex XLC is for extreme overclockers who want as few limits as possible on their overclcoking. With the ability to run to DDR2-1300 it allows great flexibility in OC settings.
  • photoguy99 - Saturday, December 9, 2006 - link

    Thanks for your help Wesley, it's just takes a little time for me to get my head around this stuff.

    Just to clarify, I think I see the answer two #2:

    If you have an unlocked CPU, the only benefit to this memory is a 5-8% performance increase.

    In this case I don't think it matters if you are an extreme overclocker - extreme as you wanna be - this is the only benefit you can ever get with this RAM with an unlocked CPU, no matter what you do.

    If you have the cash, nothing wrong with a small performance bump for $300 extra - I am not judging anyone who buys this, just trying to clarify.

    regards,
    pg

  • cmdrdredd - Friday, December 8, 2006 - link

    Why is there no 1T memory results testing? The bandwidth scores from this memory even at DDR2-1300 are pathetic to say the least. My Current system with 2Gb crucial DDR2-667 10th anniversary running DDR2-1000 at 5-4-4-8 gets 7607 Int/7631 Float buffered scores with Sandra. This is on a P5B Deluxe with E6400 running 3.2Ghz (400x8)
  • Wesley Fink - Saturday, December 9, 2006 - link

    We try to get memory as close to stock speed and multipliers as possible in our testing, which yields comparable data but not the higher bandwidths you are seeing at extremely high bus speed overclocks. End users can get high numbers with overclocking, which are great for ego comments, but that tell us very little about comparative performance. Run your memory at the same settings and compare bandwidth. Those are numbers that relate to memory comparisons. This memory will run at 8x400 just like you are using and bandwidth will be similar to what you are seeing.

    The standard bandwidth scores at DDR2-1300 are pretty much in line with expectations, but the unbuffered scores are extremely low. We don't yet have an answer for why that is the case on the 680i but we are trying to find answers. The 680i runs a 2:3 ratio at that speed, where the 975X is running 1:2 at its highest speed. The underlying "strap" can make a huge difference in apparent memory performance and it is usually programmed by the board maker, and not always visible or adjustable to the end user.

    1T is useful for a very small performance increase on some boards, generally below DDR2-800. However, that option is not available on all boards and it really makes a small differenc on current DDR2 platforms. The differences you are seeing in bandwidth are the result of high FSB overclocks and not 1T.
  • Hulk - Friday, December 8, 2006 - link

    I for one feel the most important part of a memory review is what timings will it run at each frequency and at what voltage?

    I realize that info is in the memory reviews but always in a little table that you must click to enlarge.

    Please put the timings/speed/voltage in a bar graph as well. Speed on the x-axis. Timings and voltage in the horizontal bar for each speed tested. We know that if the memory works at a certain frequency/latency/voltage the performance will be the same for any stick at those conditions.

    Better yet, tell me how fast it will run 4-4-4-12 and 5-5-5-18, as well as a few other timings.

    But as always the reviews are great. Thanks for your hard word.
  • yyrkoon - Friday, December 8, 2006 - link

    I'm curious, if the savvy enthusiast used chilled air in place of water, what the end results would be. I don't think it would be hard to built something that forced cool air through these memory sticks instead of water. i.e. Chilled air in, and hot air vented out.

    End result should be a cooler safer system overall.
  • Griswold - Saturday, December 9, 2006 - link

    Other than "for shits and giggles" I see no point in doing that. Water will do a better job. Remember, air is such a bad heat conductor, compared to water.

    A properly installed watercooling system is also very safe.

Log in

Don't have an account? Sign up now