#Law of Diminishing Rtns
16 messages in this thread
Do you have an opinion as to whether or not the difference in price
between a 68040 accelerator board at 28 mc justifies buying it over a 68030
accelerator at 50 mc?
Recreational use only, as opposed to earning income from its use.
3D Rendering and Animation programs viz Caligari and Imagine! in
particular.
I'm thinking particularly of GVP products, since an 040 accelerator for
the A2000 has been all but announced. The 40 ns chips their boards call
for are *much* more salty than the 60 ns chips they use in their 68030 50
mc. ….like about 3 times the price!
I guess what I'm really asking is: How much faster is the 68040 at 28
mc than the 68030 at 50 mc, assuming the same manufacturer, and use with 3D
rendering programs where FP math may make a difference.
Regards Tom (via Whap!)
Tom,
Supposedly (I haven't run any tests…can't afford to <grin>) the
'040 is twice as fast as a '030. Thus, a 28 MHz '040 would be equal to a
56 MHz '030.
Also, be aware there are some incompatabilities between the '040
and the '030. My memory says in particular the build in MMU and FFP calls
are different. I could be wrong on those two.
Don
Don:
OK. That's what I'm thinking… the 040 by a nose, but with many more
compatibility problems, to say nothing about the cost. Speaking of
which…… I thought you Sysop/Guru types had all this neat hardware
raining down upon you like manna from heaven, so that you might comment
favorably upon it online. 😎 😎 😎
Regards Tom (via Whap!)
Tom,
Gee…I wish manufacturers though like you <grin>!
Don
Don't forget what `040's do when running self-modifying code — BOMB.
Powerpacked and Imploded executables qualify as "self modifying," I
believe.
Brian
– via Whap!
Is that true????!!!??? Imploded files are considered "Self Modifying" and
won't run at all on an '040??? This is terrible! Please Please Please
don't let it be true… *SOMEONE* let me know, as I am considering
purchasing an '040 board for my 3000.
-Sam
Sam,
quick query, why the heck would you _want_ to use imploded program files
on a system with an '040. If you can afford that, you should definitely be
able to afford the 20 or so Meg of HD space required for unimploded files
(and that's assuming a humongous amount of imploded files).
<scratching my head in Ca.>
Brian Bartlett
Because I gain more than 20 or so MEG when I implode. I have a 100MB HD
right now and EVERYTHING is imploded (If you do not already know, most all
th stuff in LIBS: L: DEVS: and *ALL* font files (not the .font) files but
the "numbered" files are executable and can be imploded.) I figure that
un-imploded, all my stuff would be about 160-170MB. In a nut-shell, *that*
is why.
Sam
Sam, yes it is true that '040 boards have trouble with "self modifying"
files but the work around is turn off Copy Back mode on the '040 Board.
There will be a slight loss in speed but not that great.
John
Guess I asked the wrong question… Are Imploder files "self-modifying"?
How much of a speed loss can be expected with copy back mode disabled?
-Sam
Imploded (files made by the program "Imploder") seem to run fine on an 040
here.
–Ben
With copy back mode on or off? -Sam
On – we've never turned it off that I know of.
–Ben
My figures using an '040 in rendering with lightwave and imagine is 3.8
times faster. I had one file that was only 2 times faster but, but I
couldn't get it to do it again.
Some of the FPU routines are in software on the '040 because the FPU is
built in. Until programs are optimized for the '040, it might only be twice
as fast at times.
–Paul
Whappin' from the Wine Country
Paul:
Do you mean by that, you opine that an 040 performs twice the speed of
an 030 for the same clock speed, given current software? And that it could
double that if it ran optimized software?
Regards Tom (via Whap!)