[Arm-netbook] The open risc v idea is good

[Luke Kenneth Casson Leighton]

On Wed, May 3, 2017 at 11:28 AM, zap <zapper at openmailbox.org> wrote:
>
>
> On 05/03/2017 01:01 AM, Luke Kenneth Casson Leighton wrote:
>> ---
>> crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68
>>
>>
>> On Tue, May 2, 2017 at 10:50 PM, zap <zapper at openmailbox.org> wrote:
>>> I assume that's going to be the third series of libre cards right? you
>>> making a lowrisc based processor and graphics, etc,
>>  more likely the fourth or fifth.  all these things happen in
>> parallel.  the one after the RK3288 to investigate is the RK3399
>> (6-core).  also i've heard that the iMX7 is out so am having a look at
>> that.
>
> RK3399... 11.0 ghz speed if you count all the four cores which are 2 ghz each and 1.5 for the other ones...
>
> wow...
>
> I wonder how much watts that processor uses...
>
> that is crazy fast. I mean really... 4GB ram too I see as the norm. which is good.
>
> on a different note though, perchance will the fourth or fifth series of libre cards support 8gb of ram or more?
>
> I bet you could even get it to 16gb if you wanted... though that wouldn't be needed. heh.

 the cost of the RAM ICs to do that are insane.  the 1GB DDR3x16 ICs
are already $10 **EACH**.

 normally a DIMM would have 8 or 16 RAM ICs, meaning that for a 4GB
DIMM you need 8x 512mb ICs, or you could do 8GB by using 16 of them.

 normally you get 2 (matched) DIMMS totalling 8GB.

 if you want *32* GB you get 2 matched DIMMs, but nobody in
"mass-production" is shipping windows PCs or laptops with 32GB of RAM
(and if they are it's DDR4)

 additionally, it would need either 2 pairs of x32 DDR RAM
controllers, or it would be necessary to do a cascade layout: a
daisy-chain of RAM ICs.... and i'm not sure it would be possible to
fit 8 RAM ICs onto the 43x78mm PCB anyway.

 bottom line it's far too expensive and quite impractical.  4GB is the
practical limit at the moment and even that's stupidly expensive
relatively speaking.

l.