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eCS 2.2 purchase

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No. Either you know somebody that lends you the USB stick that has ArcaOS 5.1 on it or you will have to buy ArcaOS. And we are back to zero.

Roderick Klein:

--- Quote from: Lars on June 09, 2022, 04:42:28 pm ---You will never know how much of system memory (RAM) is mapped below the 4 GB physical address line.

Newer systems tend to reserve a lot of the physical memory space below 4 GB presumably for the PCI(e) bus so that you can use older 32-bit PCI cards/devices, potentially requiring large amounts of physical address space (like, say a 32-bit PCI graphics card with 2 GB of video memory: it needs 2 GB of physical address space below the 4 GB address line). Newer 64-bit PCI cards are of course not suffering from this problem.

It's just a fact that every modern OS is 64-bit by now, which means, it has no problem accessing system memory if it is mapped to physical addresses beyond 4 GB and therefore it is not affected by this limit. And therefore manufacturers no longer care about this limit.

--- End quote ---

Testing ArcaOS 5.1. beta (I am on the tester team) I have seen systems where all PCI devices have 64 bit MMIO addresses (I had one of these laptops). The UEFI loader remaps these back to 32 bit MMIO address ranges. Now the video card could be an issue using a lot of memory below the 4 GB. However more and more video cards have something called PCI bar resizing. This *might* help de amount of reserved RAM be reduced. When I have such a laptop I will test again and see if that is indeed the case.

Roderick Klein


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