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Syko · 22 February 2003, 13:16

Gee! All this from one little bit...

Toni's absolutley right about the ram under JIT in UAE, he should know he wrote it! So please dont try to argue!

However I was talking about the fast RAM on my cyberstorm Mk II which is physicaly right next to the CPU, and has the highest priority of any RAM in the system.

As it is physicaly tightly coupled to the CPU, and there is no off-board access required it is the fastest RAM in the system for responce times and for susstained r/w access.

The same is true of any other accelerator RAM that is set up in the same way. Which is most of them..... Almost all Z3 RAM is set up in this way, appart from RAM which is on expansion cards - such as SCSI controllers.

The logical distribution chart which trodas is using makes no allowance for the physical location of the RAM, and thus makes no difference in it's speed of access.

And finaly..... for Paul who wandered into an ongoing argument/discussion/crash;

the A1200 has as standard 2MB of RAM, all of which is chip RAM, i.e. it can be accessed directly by the custom chips without the help of the CPU. As a result, this RAM is slower to respond to the CPU's requests.

Any expansion RAM is accessed faster than the chip RAM, because the CPU doesn't have to wait for the custom chips. Thus you get chip RAM and fast RAM, and that's why you have to have full chip RAM before you can have fast RAM. Just to really complicate things, there's 24bit fast RAM and 32bit fast RAM! So don't worry if you're still confused.

22 February 2003, 13:16	#21
Syko Now got GSX750F :)) Join Date: Jun 2002 Location: Halifax UK Age: 60 Posts: 584	Gee! All this from one little bit... Toni's absolutley right about the ram under JIT in UAE, he should know he wrote it! So please dont try to argue! However I was talking about the fast RAM on my cyberstorm Mk II which is physicaly right next to the CPU, and has the highest priority of any RAM in the system. As it is physicaly tightly coupled to the CPU, and there is no off-board access required it is the fastest RAM in the system for responce times and for susstained r/w access. The same is true of any other accelerator RAM that is set up in the same way. Which is most of them..... Almost all Z3 RAM is set up in this way, appart from RAM which is on expansion cards - such as SCSI controllers. The logical distribution chart which trodas is using makes no allowance for the physical location of the RAM, and thus makes no difference in it's speed of access. And finaly..... for Paul who wandered into an ongoing argument/discussion/crash; the A1200 has as standard 2MB of RAM, all of which is chip RAM, i.e. it can be accessed directly by the custom chips without the help of the CPU. As a result, this RAM is slower to respond to the CPU's requests. Any expansion RAM is accessed faster than the chip RAM, because the CPU doesn't have to wait for the custom chips. Thus you get chip RAM and fast RAM, and that's why you have to have full chip RAM before you can have fast RAM. Just to really complicate things, there's 24bit fast RAM and 32bit fast RAM! So don't worry if you're still confused.