How Cyberstorm Mk-II 040 and Warp Engine 4040 Boards Address RAM on Amiga 4000

[TribbleSmasher]

I am not an expert, but the motherboard RAM seems to be accessed with motherboard speed while the RAM on the CPU card might be driven by any speed the CPU on that card wants to, including bursts etc..
So the speed of the turbo card RAM is almost always faster by factors, hence the term 'turbo card'.

[TribbleSmasher]

No, all RAM gets prioritised during bootup.
Faster RAM gets higher, slower gets lower priority.
Therefore it is perfectly fine to add e.g. 2 BigRAM256 or ZoRRAM to your Zorroslots even they are much slower than turbo card RAM.

[TribbleSmasher]

Any Autoconfig card that adds RAM follows AutoConfig, obviously. Otherwise the RAM has to be added to the system via different methods, like software ('addmem').
There is also a dedicated ROM routine that checks all memory address areas designated for, well, memory, aka RAM.
see
http://amigadev.elowar.com/read/ADCD_2.1/Hardware_Manual_guide/node00D3.html etc.

It is possible to add memory on a graphics card to be used as common RAM, but it will be slow, as it is not directly attached to the CPU bus, especially if a turbo card is used.

[TribbleSmasher]

I think the routines in ROM just poke around the address space in steps of 512kB and if the CPU does not throw a TRAP then there is some memory, i guess.