Gavinmc42 wrote: ↑
Sun Jul 07, 2019 9:15 am
Does that mean the SOC can address 24 GB ? There may be an off by one error in my math and there are probably no suitable packages with 24 GB available so let's say 16 GB would be possible?
24GB would be 8 of those 3GB DDR's in the iPhone X or 6 x 4GB chips from the Pi4B4.
No room on the PCB to place and route that many chips.
We will probably need to wait for the next DDR improvements?
As has been stated on other threads, the maximum memory size on the Pi 4 is currently limited by the availability of LPDDR4 chips. The largest size of LPDDR4 RAM chip currently available is 4GB, therefore this is also the maximum RAM size of the Pi 4. If, or perhaps when, LPDDR4 chips with an 8GB capacity becomes available, then there may
be an 8GB version of the Pi 4 released. Similarly with 16GB chips. As has been stated on another thread, the maximum RAM which the BCM2711 can address is 16GB.
Note that LPDDR5 is new as of 2019 and there are not many devices which use it yet. Modifying the BCM2711 to use LPDDR5 memory instead of LPDDR4 memory would be rather expensive, and would be a bit pointless at this stage, especially since it was just bumped up from the LPDDR2 interface on the BCM283x series.