1080ti memory speed question

[spoony77]

Sorry if this is a nooby question but i'm a bit confused.
The gpu I have (EVGA SC2) is advertised as having a memory speed of 11010Mhz, yet GPU-Z is showing the memory as 1376Mhz and Heaven benchmark is showing it as 5585Mhz?
These figures are all wildly different!

 

[Kaapstad]

Sorry if this is a nooby question but i'm a bit confused.
The gpu I have (EVGA SC2) is advertised as having a memory speed of 11010Mhz, yet GPU-Z is showing the memory as 1376Mhz and Heaven benchmark is showing it as 5585Mhz?
These figures are all wildly different!

It is actually running at 2752mhz.

GPU-Z 1376 x 2 = 2752mhz

Advertised speed 11010/4 = 2752mhz

And heaven 4 often gets it wrong by a few MHz 5585/2 = 2768mhz

 

[spoony77]

Oh that's a relief thanks for the quick response

 

[Sasahara]

More detailed explanation.

GDDR5X can run in to modes, double data rate and quad data rate mode. GDDR5 only has double data rate mode.

So GDDR5X is really clocked X2 for double data rate and then X2 again for quad data rate.

2752 x 2 = 5504 x 2 = 11008

Since DDR3, ram also has double the data lines which is why in GPU-Z you are seeing 1376 as that is showing the speed of 1 data line even though there are 2.

So 1376 x2 = 2752 x 2 = 5504 x 2 = 11008.

Hope that makes sense.

 

[spoony77]

It does thank you for the detailed explanation :thumbs-up: