Ddr3 1066 question

[ArtificialDream]

i was wondering, i saw some cpu-z screenshots of the stock x3 720 and the default bus speed is at 200mhz. does this mean that the best option for this processor is a ddr3-1600(or higher)? since i've read that amd procs are best at a 1:1 fsb-ram ratio?

 

[Crashman]

i was wondering, i saw some cpu-z screenshots of the stock x3 720 and the default bus speed is at 200mhz. does this mean that the best option for this processor is a ddr3-1600(or higher)? since i've read that amd procs are best at a 1:1 fsb-ram ratio?

DDR-400 would be 1:1, but the CPU doesn't support DDR1. DDR2-800 is 1:2. DDR3-1600 is 1:4

 

[ArtificialDream]

isn't ddr3-1600 clocked at 200mhz, same as x3 720 stock fsb? how come it's at a 1:4?

 

[Crashman]

isn't ddr3-1600 clocked at 200mhz, same as x3 720 stock fsb? how come it's at a 1:4?

The bus for DDR3-1600 runs at a data rate of 1600 MHz, and a clock rate of 800 MHz. DDR3 stands for DOUBLE data rate, revision 3. If it ran at 200 MHz bus clock and had a 1600 MHz data rate, it would be called "Octo data rate"

 

[ArtificialDream]

The bus for DDR3-1600 runs at a data rate of 1600 MHz, and a clock rate of 800 MHz.

it's much larger than the x3 720's bus rate? pardon for the noobish question, but from what i've read, the author says that when tweaking the FSB of your processor, one should be careful not to go past the clock speed of one's ram. here's an excerpt:


Well, as I said before, when you raise the FSB, you effectively overclock everything else in your system. This applies to RAM too. RAM that is rated at PC-3200 (DDR 400) is rated to run at speeds up to 200MHz. For a non-overclocker, this is fine, since your FSB won't be over 200MHz anyway.

Problems can occur, though, when you want to raise your FSB to speeds over 200MHz. Since the RAM is only rated to run at speeds up to 200MHz, raising your FSB higher than 200MHz can cause your system to crash. How do you solve this? There are three solutions: using a FSB:RAM ratio, overclocking your RAM, or simply buying RAM rated at a higher speed.

how does this fit to ddr3s? thanks again!

 

[Crashman]

it's much larger than the x3 720's bus rate? pardon for the noobish question, but from what i've read, the author says that when tweaking the FSB of your processor, one should be careful not to go past the clock speed of one's ram. here's an excerpt:


Well, as I said before, when you raise the FSB, you effectively overclock everything else in your system. This applies to RAM too. RAM that is rated at PC-3200 (DDR 400) is rated to run at speeds up to 200MHz. For a non-overclocker, this is fine, since your FSB won't be over 200MHz anyway.

Problems can occur, though, when you want to raise your FSB to speeds over 200MHz. Since the RAM is only rated to run at speeds up to 200MHz, raising your FSB higher than 200MHz can cause your system to crash. How do you solve this? There are three solutions: using a FSB:RAM ratio, overclocking your RAM, or simply buying RAM rated at a higher speed.

how does this fit to ddr3s? thanks again!

You quoted an article that already tells you that DDR-400 (PC-3200) runs at 200MHz. The DDR3-1600 bus is four times the data rate and runs at 800 MHz. This means it's running at a ratio of four times your processor's HT clock.

It doesn't hurt anything, but I can't really see any reason why you would need RAM that fast. I just don't think it will help anything. I haven't seen significant performance gains for AMD processors running anything higher than DDR2-1066.

 

[ArtificialDream]

oh. everything's clearer now. thanks for all the answers!

 

[ArtificialDream]

Best answer selected by ArtificialDream.