How to check the amount of RAM: 512MB or 1GB?

[Jérémie Astori]

Hello guys,

I just received a few seconds ago 2 wonderful Cubieboard and I am thrilled to play with it!

I just have one concern: there are 2 RAM chips on each Cubieboard, each chip saying 256X16DDR3. That is, to me, 256MB x 2 = 512MB and not 1GB...
For information I have bought them on Exp-Tech, explicitly saying "DRAM: 1GB DDR3 @ 480MHz".

The information I found on the Internet does not really clarify the situation.

Could someone tell me if I am wrong?

Thanks a lot!

[Roman Mamedov]

On Thu, 14 Feb 2013 03:26:17 -0800 (PST)
Jérémie Astori <jer...@astori.fr> wrote:

> Hello guys,
>
> I just received a few seconds ago 2 wonderful Cubieboard and I am thrilled
> to play with it!
>
> I just have one concern: there are 2 RAM chips on each Cubieboard, each
> chip saying 256X16DDR3. That is, to me, 256MB x 2 = 512MB and not 1GB...

256 * 16(bit, or two bytes) * 2

or 256*2*2 = 1024.

> For information I have bought them on Exp-Tech, explicitly saying "DRAM: 1GB
> DDR3 @ 480MHz".
>
> The information I found on the Internet does not really clarify the
> situation.
>
> Could someone tell me if I am wrong?
>
> Thanks a lot!
>

--
With respect,
Roman

[Jérémie Astori]

Oh, I'll answer this one to myself. It may be useful for some future Cubiboarders, although I admit I didn't think enough at first :D

256X16DDR3 means 256 x 16 = 4096 megabits, which are 512 megabytes... 2 chips means 2 x 512 = 1024 megabytes = 1 GB...

My bad, sorry!

Thanks, Jérémie

[Jérémie Astori]

Yup, that's what I figured out afterwards, confusion between  bytes and bits... :-)
Thanks for the effort!

Jérémie