Hi! I read about a 1,5 GB ram limit in morphos.
Why?
Thk you!!

Quote:

If I am not mistaken, it is related to the 31 bit address limitation.

31 bit = 2 GB becaus of amiga legacy and compatibility with old apps
0,5GB - 1GB because of pci addres space, depending on machine. Or simply you can not have more memory bank.

max mem for example:

PEGs: 1,5GB ram
efika 0,256GB ram
Powermac g4, Pbook: 1,5GB
macmini g4: 1GB (only onebank)
Powermac g5 1GB (too much pci address space)



[ Edited by Derringer 17.11.2013 - 06:18 ]

Quote:

The EFIKA only has 0,125GB RAM.

Btw:
EFIKA hardware-layout is designed for 512MB and it would be possible by upgrading frmware. (bplan has planed such versions of EFIKA.....). Unfortunately bplan never releases such a firmware-upgrade......

@Derringer,

Did you try recently, or by the past, to boot and then to use a pegasos 2 with 1,5 gb of memory ? If it booted did it freeze randomly, without reason, frequently ? On a little book of bplan joined with my pegasos 2, only in german, the maximum amount of memory they recommend to use is 1 gb or 2 x 512 mb.

Brumiga

@Brumiga

Peg2s can in theory handle 2x1GB but that only works in the last revision (and even tere it's hit and miss).
AFAIK mixing different sized modules would make things even worse.

On a Peg2 working with 2GB you'd still only get 1.5GB reported by MorphOS (31Bit - 512MB for PCI).

-> for more than 1GB, get a Mac (PowerMacG4, PowerBook or iBook).

Quote:

Actually according to the 5200b documentation, there are two CS channels available - the first is enabled by default (and populated on the EFika with two 64MB chips), the second is enabled by setting a register bit iirc (which is probably the 'firmware update') referred to.
It should be possible to upgrade the Efika to 256MB without any firmware modifications, however this would require two 128MB chips to be soldered in place of the existing two 64MB ones. The 5200b autoconfigs the memory on startup iirc, so shouldn't require any firmware mod to address the larger capacity chips.

The only 128MB chips I could find (Micron MT46V64M16-P6t) were around $95 per chip last I checked... obviously this would have impacted somewhat on the Efika's $199 original price point (later reduced to $99), which is no doubt why bplan chose 128MB only.
I haven't yet shelled out, and they might not even be available anymore, but I'm still considering buying them anyway just for the hackery and bragging rights on a 256MB Efika.

Adding two additional 64MB chips would no doubt be cheaper, but would require the firmware modification (and addition of accompanying SMD components on the underside of the PCB).

Brumiga,
Quote:

I already sold my peg2 years ago, but with two same 1GB modules it was stable. I tried at that time with many different brand in it. I thought i just put wrogn modules, or not the right type memory modules in it, becauese system can't see th full 2GB memory size.

Regarding memory & Peg2, browse through this thread for some info.

http://www.powerdeveloper.org/forums/viewtopic.php?f=1&t=1301