Question RAM sodimm pc2 6400 running at 667 mhz and 3066 Mb/s?

[frariky]

Hi,
I have a Dell Vostro 1700 with a cpu T5870.
I installed 2 modules of pc2 6400 sodimm ram (2 x 2GB) and the laptop is now running the ram at 667 mhz and 3066 MB/s.
OS is Windows 10 64bit.
The system recognises all the 4GB of RAM.

Is this right?

I was expecting much more speed instead of 3066 MB/s.
Frequency of the RAM is 800 mhz but I think the cpu T5870 can't do better (in the bios it is set at 667 mhz)
I'm aware that in the bios I can't change the settings of the frequency of the ram.

Thank you

 

[Phaaze88]

Memory runs in DDR(dual data rate), so 667 * 2 = 1334mhz.
Nothing else to be done about it in a locked board. All faster kits will just default to 1333mhz.

 

[frariky]

Memory runs in DDR(dual data rate), so 667 * 2 = 1334mhz.
Nothing else to be done about it in a locked board. All faster kits will just default to 1333mhz.

Thank you for your reply, is this also valid for the speed: 3066 Mb/s * 2 = 6132 Mb/s?

 

[Phaaze88]

No. That's just the data transfer speed.

 

[frariky]

No. That's just the data transfer speed.

Thanks again
Is it normal I have a speed of 3066 Mb/s with a ram pc2 6400?
This is my main doubt.
I was expecting at least 5000 Mb/s that is the equivalent of a ram pc2 5300
If I'm not wrong, a speed of 3066 Mb/s isrelated to a ram pc2 3200

 

[TJ Hooker]

I installed 2 modules of pc2 6400 sodimm ram (2 x 2GB) and the laptop is now running the ram at 667 mhz and 3066 MB/s.

Where are you seeing these values reported?

Please download CPU-Z and post screenshots of the Memory and SPD tabs.

 

[frariky]

Where are you seeing these values reported?

Please download CPU-Z and post screenshots of the Memory and SPD tabs.

 

[TJ Hooker]

So your sticks are rated for running at 800 MHz effective speed, but they're currently running at ~666 MHz (double the memory clock value shown, due to DDR = Double Data Rate). You could try going into the BIOS and see if you can change the speed, but I doubt your laptop will have this option.

This corresponds to a max theoretical bandwidth of 10667 MB/s in dual channel.

 

[frariky]

So your sticks are rated for running at 800 MHz effective speed, but they're currently running at ~666 MHz (double the memory clock value shown, due to DDR = Double Data Rate). You could try going into the BIOS and see if you can change the speed, but I doubt your laptop will have this option.

This corresponds to a max theoretical bandwidth of 10667 MB/s in dual channel.

Thank you for your answer, I wish I had 10667 Mb/s but with Novabench (and also Memtest86) I get the speed of the ram of 3311 Mb/s.
This it the "mystery" that is haunting me

 

[TJ Hooker]

Thank you for your answer, I wish I had 10667 Mb/s but with Novabench (and also Memtest86) I get the speed of the ram of 3311 Mb/s.
This it the "mystery" that is haunting me

Emphasis on max theoretical bandwidth. That doesn't mean you're ever going to see values that high in the real world.

 

[frariky]

Emphasis on max theoretical bandwidth. That doesn't mean you're ever going to see values that high in the real world.

Thank you, I now can say my pc6400 ram is working properly like a pc 5300 (due to the bios/cpu setting that can't be changed).