Is my memory working right?

By sjps220
Jan 29, 2006
  1. I am a little confused about the memory in my system. I have the OCZ PC-3200 DDR400 Premier Series 1GB (2x512MB) Dual Channel Kit. So the 400 is 400 MHz right? When I run cpuz it says that the frequency is 201 MHz. Why is that?

    I read in another thread that it can have something to do with the cpus FSB? I don't really understand FSBs too well. Is it the same as HTT? I have an athlon 64 3500+ venice and my motherboard is the standard A8N-SLI.

    I'll attach my cpuz results.
  2. Vigilante

    Vigilante TechSpot Paladin Posts: 1,666

    I'll just comment from memory (pun intended ;).

    The function of DDR (Dual Data Rate, or Double Data Rate as some might like) allows it to work in "both directions" of the communications link. Because of this dual mode, it effectively doubles the transmissions rate (200mhz), hence 200mhz is effectively 400mhz. Think of it as an "up and down" square wave form. Old RAM only did an operation on the "up" end of the wave. DDR does operations on the up AND down waves. Thus doubling whatever transmission rate is set.

    That is a pretty crude explanation I know. But basically this is the way it works for any DDR RAM speed, the FSB is doubled.

    There is a connection between the CPU and RAM through the FSB. Your CPU (as noted in your txt file), has a "multiplier" of that FSB. Your FSB is 200mhz, so your DDR is effectively 400mhz, and your CPU, with multiplier of 11, is 2200mhz. So 200x11=2200mhz, which is the core speed of your 3500+ CPU. See how it works now? The 3500+ A64 runs at 2.2ghz, or 11 times the 200mhz FSB. While your DDR RAM can only double this amount to 400mhz.

    Putting your RAM in "Dual Channel" mode helps too, as it enables the second memory channel of the 3500+. A boost in performance over the 3400+ which didn't have a second channel in the memory controller. So you are getting more performance using your RAM in Dual Channel mode.

    If you have any more questions, feel free to ask!
  3. sjps220

    sjps220 TS Rookie Topic Starter Posts: 106

    oh okay! Perfect! I was just reading another thread where someone was talking about the effects of changing the speed of the ram so I checked mine and saw 200 and assumed it was set to the wrong speed. Thank you for the thorough explanation. So because it lists the memory at 201 MHz, and the multiplier is 11, it lists my cpu at 2211 MHz! It all makes sense.
  4. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    If I can just step in and say....


    Nice post vigilante. :grinthumb
  5. Vigilante

    Vigilante TechSpot Paladin Posts: 1,666

    Thanks guys, well I'm sure someone can think of a better term then "up and down square wave". LOL

    The part about 3400+ and 3500+ memory channels I looked up. But would make a pretty good buying choice between the two, as from what I read, the 3400+ doesn't take full advantage of running in Dual Channel mode. Hmm. While the 3500+ has a built in 2nd memory channel, which only works when you have 2 DRAMs installed (thus dual channel).

    Good stuff.

    sjps220 - So 201mhz huh? You are overclocking by 1mhz! lol
  6. sjps220

    sjps220 TS Rookie Topic Starter Posts: 106

    Oh yeah, I'm pretty hardcore like that. Always pushing the envelope!

    Thanks again for the help. Glad to hear the 3500+ handles dual channel better.
  7. mephisto_007

    mephisto_007 TS Guru Posts: 224

    Sorry if I'm off topicz, anyway how do we know how to take advantage of running in Dual Channel mode? I am using a Intel Pentium 4 2.8GHz (Prescott) - Gigabyte 8IG100-G mainboard.
  8. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    You can confirm if your motherboard supports dual channel ram by checking the manual/maker website. If it DOES support dual channel, then you have to be sure you have your (ideally identical) 2 (or 4) sticks of ram in the right slots.

    To confirm that you are in fact running in dual channel mode, you can download and run this program:

    click the "memory" tab and have a look at what it says under "# channels". If it says dual, you're good to go.
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