Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!cbmvax!daveh
From: daveh@cbmvax.commodore.com (Dave Haynie)
Newsgroups: comp.sys.amiga.tech
Subject: Re: A2620/30
Message-ID: <9348@cbmvax.commodore.com>
Date: 15 Jan 90 21:51:17 GMT
References: <1990Jan12.222613.28109@athena.mit.edu>
Organization: Commodore, West Chester, PA
Lines: 56

in article <1990Jan12.222613.28109@athena.mit.edu>, rlcarr@athena.mit.edu (the Wizard of Speed and Time) says:
> Summary: any problems?
> Xref: cbmvax comp.sys.amiga.tech:9947 comp.sys.amiga:49795

> (1) Will the A2620 allow you to boot off the 68000?  What about the A2630?
Yes.  Yes.  Both give you a menu if you reboot the system while holding down
both mouse buttons.

> (2) Can KickStart ROM be copied to the 32 bit ram on the A2620?  What about
>     the A2630?
Yes. Yes.

> (3) How much faster (overall, graphics, hard drive I/O,
>     and math grinding) is the A2620 compared to my A2000?   How about
>     the A2630 compared to my A2000?  The A2630 compared to the A2620?
With a FASTROM in place, your overall system speedup is roughly 4x with an
A2620, 8x with an A2630, but it does vary depending on what you're doing.
Any floating point intensive applications that offer FPU coded versions may
run 25x-50x faster than on a stock 2000.  Both integer and floating point
stuff on the A2630 is about twice the speed of the A2620 (FPU stuff would
be a bit better than this is the program is written with the 68882 in mind).

> (4) What kind of RAM does the A2620 use?  The A2630?  How hard is it to find?
>     How hard to install?
They both use 256k x 4, 100ns, ZIP package, 414256 or similar DRAM.  I've never
had to find it on my own; it's a solder-in job, not too difficult for anyone
with reasonable soldering experience, but not what I'd call a beginner's job.

> (5) If I someday ever want to run Amiga UNIX, can I run it with an A2620?
>     How about with an A2630 (assuming I get a big enough hard drive,of course)?
With enough memory and hard disk space, it's supposed to run on both.  I suppose
the UNIX people will have a list of requirements or some such when appropriate,
but the basic requirement is certainly the 32 bit CPU + MMU.

> (6) Can I put hard drive buffers in 32bit ram?  (7) Does the 32bit RAM autoconfig?
Yup, the 32 bit RAM can be accessed by DMA, and it autoconfigures.

> (8) will the A2620 be able to access my 4 meg of fast ram?  What about
>     the A2630?
They both use the first 2 or 4 megs of autoconfiguration space for their 32 bit
memory, leaving 4 megs of space for more memory, bridge card, whatever.  If all
you have is 4 megs of 16 bit memory, that's no problem.

> (10) is there any way to force a program to be placed in 32 bit RAM?
>      can you force a program into 16 bit RAM?
The OS doesn't really differentiate.  The 32 bit memory will be first in the
memory lists, based on how autoconfig currently does things, and as such it's
the first to get used.  Some RAM disks automatically allocate from the end of
memory, and would get 16 bit memory in such a system.  This is just the way
things happen to work, though, nothing's forcing the issue.

> Rich Carreiro - Most Biased Boston Celtics Fan!   "So long, farewell, and may
-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
                    Too much of everything is just enough