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ok guys U have 4 gigs of crucial ballastix 6400 and below is a link to the ram settings. My question is my Dram Frequency is 350 I thought it is suppose to be 800 mhz? Is my ram set correctly or not?
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Noob memory clock setting question
- Thread starter fantome2024
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(cf)Eclipse
Freelance Overclocker
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ddr2-800 is 400mhz. double the actual speed to get the "rated" speed, because it's "double data rate". just blame stupid marketing 
however, 350mhz is still 50mhz shy of the rated speed. have you done any overclocking in the bios? what is your system?
however, 350mhz is still 50mhz shy of the rated speed. have you done any overclocking in the bios? what is your system?
BillParrish
Supreme [H]ardness
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Well its not so much that it is incorrect as it is that you are not getting advantage of your memorys full speed/bandwidth.
Idealy it should be at 400MHz clock (800MHz data rate - date transfered on rising and falling edge of each clock pulse so data rate is 2 x clock rate which is what its called, wait for it, Double Data Rate DDR ram. )
Now most intel board (Nvidia chipsets are different and you did not say which you had) work like this:
EVERYTHING is run off of the FSB clock.
The cpu will run at the cpu multiplier x FSB clock = cpu frequency
The memory will run at 1 x the FSB = memory clock ( x2 for memory data rate)
[so for your 800MHz PC6400 memory the clock should be 400 in cpu-z]
Most boards have memory ratios/multipliers to help match memory speed to the memory spec.
Since I have no details lets make some stuff up that might be somthing like what is happening to you.
Lets say you had a cpu that normally runs at 8 x 333 = 2.6GHz and with normal defaults your memory would get set to 333 MHz and give you a 667MHz data rate which is underclocked and not taking advantage of your memory speed you paid for. You would normally just look in the memory settings and select a memory multiplier that would boost memory speed but leave the cpu alone. A 1.2 memory mulitplier (might be listed as 4:5 or 5:4 check your manual) would make the memory run at 333 x 1.2 = 400MHz clock 800MHz data rate and your memory is now perfectly on spec.
Trouble with above is that it is all stock.
lets say you have raised the fsb to 350 to OC your CPU, which is now running at 8 x 350 = 2.8MHz and now your memory is running at 350 clock and 700MHz data rate. Cpu faster, memory still underclocked. But now you have to be carefull with which multiplier you choose if you can even find one that will do what you want. The 1.2 is typically the lowest (other than the default 1:1) so either you live with your memory underclocked,and cpu MHz are much much more powerfull than memory MHz so that is not as bad as it sounds, or you make a mulitplier work. In this case if you used the same 1.2 your memory clock would be 350 x 1.2 = 420MHz clock 840MHz data rate which is a slight OC of your memory and in most cases would be ideal - IF your memory could handle the OC. Right around that 420 is where most PC6400 ram would need a little extra voltage or perhaps loosen the timings a bit. You just have to test and see.
Summary:
Raise the FSB as high as you can to get the CPU as fast as you can on a C2D system. Then go back and find a memory mulitplier and ram settings that will run your ram stable at or just over its rated speed. (or you can test and see just how high it will go, Memtest86+ is your friend.
Idealy it should be at 400MHz clock (800MHz data rate - date transfered on rising and falling edge of each clock pulse so data rate is 2 x clock rate which is what its called, wait for it, Double Data Rate DDR ram. )
Now most intel board (Nvidia chipsets are different and you did not say which you had) work like this:
EVERYTHING is run off of the FSB clock.
The cpu will run at the cpu multiplier x FSB clock = cpu frequency
The memory will run at 1 x the FSB = memory clock ( x2 for memory data rate)
[so for your 800MHz PC6400 memory the clock should be 400 in cpu-z]
Most boards have memory ratios/multipliers to help match memory speed to the memory spec.
Since I have no details lets make some stuff up that might be somthing like what is happening to you.
Lets say you had a cpu that normally runs at 8 x 333 = 2.6GHz and with normal defaults your memory would get set to 333 MHz and give you a 667MHz data rate which is underclocked and not taking advantage of your memory speed you paid for. You would normally just look in the memory settings and select a memory multiplier that would boost memory speed but leave the cpu alone. A 1.2 memory mulitplier (might be listed as 4:5 or 5:4 check your manual) would make the memory run at 333 x 1.2 = 400MHz clock 800MHz data rate and your memory is now perfectly on spec.
Trouble with above is that it is all stock.
lets say you have raised the fsb to 350 to OC your CPU, which is now running at 8 x 350 = 2.8MHz and now your memory is running at 350 clock and 700MHz data rate. Cpu faster, memory still underclocked. But now you have to be carefull with which multiplier you choose if you can even find one that will do what you want. The 1.2 is typically the lowest (other than the default 1:1) so either you live with your memory underclocked,and cpu MHz are much much more powerfull than memory MHz so that is not as bad as it sounds, or you make a mulitplier work. In this case if you used the same 1.2 your memory clock would be 350 x 1.2 = 420MHz clock 840MHz data rate which is a slight OC of your memory and in most cases would be ideal - IF your memory could handle the OC. Right around that 420 is where most PC6400 ram would need a little extra voltage or perhaps loosen the timings a bit. You just have to test and see.
Summary:
Raise the FSB as high as you can to get the CPU as fast as you can on a C2D system. Then go back and find a memory mulitplier and ram settings that will run your ram stable at or just over its rated speed. (or you can test and see just how high it will go, Memtest86+ is your friend.