@Maijestro
Quote:
Can AmigaOs4.1 access 4/8 GB of memory at all or is the maximum usage 2GB?
For 99% of the software on AmigaOS 4.1 the limit is still 2 GB, using more requires adding support for the "ExtMem" feature in the software.
For example the "RAM Disk:" handler supports it, i.e. for files you copy to RAM: it doesn't use the first 2 GB, which all software can access, but can use the upper 2 GB instead software not supporting ExtMem can't use.
Special note for your QEmu setup: ExtMem isn't supported in the Pegasos 2 kernels, no matter if real or emulated hardware.
I don't know why, but probably differences to U-Boot or bugs in the hardware/DIMM setup of the Pegagsos 2 SmartFirmare for more than 2 GB RAM.
More than 4 GB is theoretically possible even on the old systems (G2, G3 and G4 CPUs support 36 bit physical address space, i.e. 64 GB RAM), but none of the 32 bit hardware (classic Amiga with Blizzard/CyberStormPPC, AmigaOne, Pegasso2) supports it. On the 4x0 CPUs it's IIRC 41 bit, 2 TB = 2048 GB RAM, but I doubt the Sam440/460 supports more than 4 GB.
Only the systems with 64 bit CPUs, X1000, X5000 and A1222, may support more than 4 GB.