Re: What is the difference between ROM 1 and ROM 3 IIgs computers?

[spec@vax2.concordia.ca (Mitchell Spector)]

In article dempson@actrix.gen.nz (David Empson) writes...

>Steve Mentzer <!smentzer@ecom.net> wrote:
>> I am never one to argue with you, but actually a ROM03 machine is *slightly*
>> faster when running GS/OS apps. The reason for this is that more of the GS
>> toolbox is rom-resident. Ram on the GS operates at ~2.5Mhz whereas the ROM
>> operates at ~2.8Mhz (due to the RAM refresh cycle). Additional toolboxes are
>> loaded in RAM on a Rom01, so the toolbox routines are slightly slower.
> 
>More than slightly.  It is quite noticeable.  The main area of
>improvement is the QuickDraw II changes in System 5.0, which are in the
>ROM in a ROM 3 machine, but must be loaded into RAM on a ROM 1 (most of
>the low-level drawing bottleneck routines).
> 
>I think there were also Window/Menu/Control manager improvments, but
>they were less significant.
> 
>All this results in noticeably faster screen updates in GS/OS desktop
>programs.

    It's worth noting that when using System 3.x (ProDOS 16) or
System 4.0 (first GS/OS release) on a ROM 3, the screen updates
also occur _much_ noitceably faster. Scrolling through windows,
opening menus and even disk boots aren't nearly as sluggish as
with the ROM 01.

>Doesn't hold a candle to a ZIP or TransWarp, though...

    That's for certain. Even with a 6 MHz TransWarp GS (lowest 
speed AE sold) on a ROM 01, the performance increase makes the 
ROM 3's advantage no longer apparent.

Mitchell Spector
spec@vax2.concordia.ca