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

[doark at mail.com]

I apologize for DOS'ing the list, I can only get online about once a week.

On Wed, 3 May 2017 11:38:26 +0100
Luke Kenneth Casson Leighton <lkcl at lkcl.net> wrote:
> 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.

But that would mean that an 8GiB stick for a desktop would cost $80 just
for the ICs. I can find 8GiB of RAM for $60 and cheaper, I bet, if I
poked my nose around.
Or maybe desktops don't need ICs???

>  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)
You write that as though being dismissive of DDR4. Why is DDR4 currently
unacceptable for one of your designs?

>  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.
Well, I bought a 4GiB RK3399 SOC card fro firefly for $200.
Don't get me wrong, I love your effort, but I need RAM, CPU power,
lots of ports, and more screen landscape.


Hmm, maybe you should invent an OpenSource IC?

Sincerely,
David