I never understood fast ram, chip ram etc.

[ricco32097]

I never understood fast ram, chip ram etc.
Can anyone please explain what is being used for what. Thanks

[shaf]

Hmm,

Chip RAM is the RAM that is accessed by the Custom Chips for Sound and Video.

Fast RAM is the expanded Memory. Some early programs were written to only use the Chip RAM especially Programs that wrote to the hardware directly.

Many early games written for KS/WB 1.0, to 1.2 only worked with Chip RAM.

This is a very simplistic explaination, I'm sure others could supply further clarification/details.

Shaf

[SamuraiCrow]

The reason Fast RAM is faster is that it isn't shared between the custom chips.  On a 7MHz system it isn't very noticable speedwise since the memory on an A1000/500/2000 is 70 nanosecond which can access at 14 MHz so the custom chips and the main processor just take turns.

The main time you have to consider Fast RAM to be useful is if you don't have enough to fit everything into Chip RAM or if you have an accelerator card.  Getting the maximum performance out of an accelerator card involves forcing as much into Fast memory as possible.

[Lando]

The Chip RAM is the RAM in the Amiga to which the custom chips have access.  So, any data which needs to be accessed by the custom chips (graphics data, copperlists, sound samples, and so on) must be in Chip RAM.

Fast RAM can only be accessed by the CPU (and so is faster because the other chips aren't vying for access).  You can still store graphics and sound in it, but they must be transferred to Chip RAM before the custom chips can access them.

The maximum Chip RAM that any real Amiga can have is 2MB (I think there's an option in UAE to have more).  You can have an Amiga with only Chip RAM (like the stock A1200 or A600).  You can't have one with only Fast RAM.

[Fransexy_]

The maximum Chip RAM that any real Amiga can have is 2MB (I think there's an option in UAE to have more)

UAE cah have up to 8 MB chip ram because the Aga chipset was created to support up to 8 MB chip ram but for save money commodore downgrade the AGA to only 2 MB chip ram.Another stupid move of commodore  :-(

[TheSLASH!]

The first Amiga I bought was a A2000 with only 2MB chip mem, some programs like a early version of Deluxe Paint III din't supported chipmem only for the animation part.

And there are also some games (that I can't remember the tile of) that also took for granted that an Amiga does have fast mem if there is more than 512kb mem, like the standard A500.

[Framiga]

and this is why they have written "NoFastMem"... ah memories! :-)

[ricco32097]

Interesting. I always thought it was just one chip of memory that then split it up into fast, chip etc.