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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: joekster on July 24, 2012, 12:30:41 AM

Title: 14mhz 68k or 7mhz 020/881
Post by: joekster on July 24, 2012, 12:30:41 AM
Trying to decide what to use in my a1000. I have an ICD adspeed and a TRR saphire to choose from. On one hand, the 14mhz 68k is going to be faster than the 020/881; but the 020/881 will let me run os 3.9, 020 optimized apps (pctask), and 881 apps (lightwave, vistapro).

Thoughts?
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Heiroglyph on July 24, 2012, 12:44:32 AM
Without local ram at the same speed, the extra MHz won't be doing much.

I'd go with the 020 for the reasons you stated.  The tiny cache on the ICD will help some, but not very much.
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Digiman on July 24, 2012, 12:59:40 AM
7mhz 020 won't make any kind of different worth opening the case for IMO.
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Terse on July 24, 2012, 12:59:50 AM
The Adspeed will be much faster.

As you note - the advantage to the 020 is that it's an 020 with an FPU.
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Matt_H on July 24, 2012, 05:31:00 AM
I didn't know 020s came in speeds lower than 14MHz. What board is that?
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Tenacious on July 24, 2012, 06:12:15 AM
Quote from: Heiroglyph;701067
Without local ram at the same speed, the extra MHz won't be doing much.

I'd go with the 020 for the reasons you stated.  The tiny cache on the ICD will help some, but not very much.


+1!  I owned an AdSpeed.  It really didn't live up to its billing speed-wise.  It was incompatible with other hardware, too.  There are much better accelerators.
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: utri007 on July 24, 2012, 06:23:56 AM
ADSpeed has a IDE controller
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Azryl on July 24, 2012, 07:32:51 AM
Nope... there were 2 versions of the ICD Adspeed, one version had 40pin IDE connector + the 7/14mhz Accelerator with 32k cache. Other was basic Accelerator only.

http://amiga.resource.cx/exp/adspeedide
http://amiga.resource.cx/exp/adspeed

If you want 68000 + FPU then the PamC versions worked well

http://amiga.resource.cx/exp/pamc500

No memory onboard tho, so more suited for A500 with sidecar expansion.

The Blizzard Memory Turbo was quite rare and the memory for it was extremely difficult to fully populate, no FPU either. But it did allow shadow ram function to copy Kickstart (any version) into it and use, quite a good feature!

http://amiga.resource.cx/exp/blizzard500

Az
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Terse on July 24, 2012, 07:33:34 AM
Quote from: Matt_H;701080
I didn't know 020s came in speeds lower than 14MHz. What board is that?

There are a few 7Mhz 020 boards. They were used for rendering and math, and really nothing else.  In all likelihood, there may have been no reason to clock even to 14Mhz, since the asyc. 68881/82 would be the workhorse.

The one this poster has is the Sapphire - a board most famous for powering the first generation full immersion Battletech simulators by FASA.

The AdSpeed seeks to solve the problem of speeding up general Amiga 500 tasks.  The tiny cache combined with the 14Mhz processor really does more or less double the processor speed of the 500.  There are also users who upgrade the 68000 with a 68010, and gaining a further 2-10% performance increase beyond the normal adspeed.
Title: Re: 14mhz 68k or 7mhz 020/881
Post by: Heiroglyph on July 24, 2012, 02:02:08 PM
Check out this thread: http://www.amiga.org/forums/showthread.php?t=62205

He's got a much faster 030 and without ram running at the CPU speed, even that's not a huge improvement.

At least with the 020 you get the newer instructions plus a math co.