2GB DDR2 PC2-6400U 800MHz not running at 800MHz

[comprehendo111]

So both of my 2GB DDR2 PC2-6400U 800MHz are not running at 800MHz they are both running at 400MHz according to CPU-Z and paired they drop down to 333MHz I assume this is a noticeable difference since its more than half slower. Is there a way to fix this or is my RAM just going bad or something?

https://gyazo.com/84fdd0c435ae2a73771ac7546cbf88ed

 

[rgd1101]

https://en.wikipedia.org/wiki/DDR2_SDRAM
double data rate

 

[comprehendo111]

https://en.wikipedia.org/wiki/DDR2_SDRAM
double data rate

So nothing is wrong can you explain a bit I don't understand

 

[rgd1101]

https://en.wikipedia.org/wiki/DDR2_SDRAM
double data rate

So nothing is wrong can you explain a bit I don't understand

ddr is x2 so 400 x2 is 800

 

[smorizio]

in real world think of a 4 lane highway. old ram the cars only went one way per red light. (400 speed). newer ram can go both directions on the same highway on each clock cycle. (ddr2 800 speed). your max speed on ram is dependent on the max ram speed there rated for. the mb chipset and cpu used on your build. in mb bios there are ram speed settings (xmp profile) see if your ram speed profile is right. on your ram make sure both stick are the same speed if there one marked slower speed then your mb is going to slow down.

 

[comprehendo111]

Yes one is only 666MHz which is why i'm getting 333MHz correct thanks glad you could clear this up for me I still don't totally understand but my BIOS I don't think has xmp profile or ram speeds it's an OEM board by HP.

Glad to know it's working properly though