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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Prmetime on September 19, 2003, 08:03:09 PM

Title: 68xxx cpu-which runs the hottest?
Post by: Prmetime on September 19, 2003, 08:03:09 PM
I'm trying to do a little research on the 68000 series of CPUs and I'm trying to figure out which run hot, warm, or cold.  If I remember correctly, the 68030 and 68040 run pretty hot while the 000, 010, 020, and 060 run quite cool (meaning they don't require a fan).  Can anyone help me out here?
Title: Re: 68xxx cpu-which runs the hottest?
Post by: mikeymike on September 19, 2003, 08:15:17 PM
040 runs the hottest I think.
Title: Re: 68xxx cpu-which runs the hottest?
Post by: x56h34 on September 19, 2003, 08:16:38 PM
From my experience:

68040 is the hottest one.
68030 and 68060 are trailing closely behind.
68020, 68010, and 68000 have never raised any concerns.

I can also confirm that some 68060 run cooler than others. For example, my Phase 5 Blizzard 1260 can get pretty hot in my desktop enclosure. I've used it with trap-door closed, and then was forced to drill holes through the plastic around where the 060 chip is in order for the heat to get out. You could not hold your finger on the 060 chip longer than 5 seconds, that's how hot it got. Even without the trap-door, it was uncomfortably hot with your finger on it. However, the DCE made 1260T model with a made in 2002 060 chip (yes, it says that on it) :-) runs probably as cool as the 68000 chip in my A500. Used it for hours one day and the heat was never an issue with it. Go figure.  :-?
Title: Re: 68xxx cpu-which runs the hottest?
Post by: Kronos on September 19, 2003, 08:18:46 PM
Well the 060 in my Blizz2060 was allways absoltue cool,and that card
came from the very 1st batch ever made by P5.

The CS_MK1 in my A4000 on the other side has that fan for a good reason ...
Title: Re: 68xxx cpu-which runs the hottest?
Post by: Karlos on September 19, 2003, 08:47:05 PM
68040 @ 40 MHz runs the hottest, hands down.

It uses a 5V core, has a high transistor count and unlike its lower voltage successor does not use a static design either. Later revisions ran a bit cooler and there were even 3.3v parts but I think these were based on the EC version.

A really good source for the information you need is the CPU user manual for each component (downloadable as pdf from motorola).
They include the thermal characteristics of these chips at different clock speeds and in different packages.
Title: Re: 68xxx cpu-which runs the hottest?
Post by: Stedy on September 19, 2003, 09:49:39 PM
From the 68K series datasheets:


68060   4.9 Watts @ 66 MHz
68040   6.2 Watts @ 40 Mhz (worst case)
68040V       2.0 Watts @ 33 Mhz (3.3V part)
68030         1.9 Watts @ 50 MHz
68020         1.4 Watts @ 33 MHz
68000         1.2 Watts @ 20 MHz

Coldfire
MCF5407   0.5 Watts @ 54 Mhz external, 162 MHz internal

The 68040 wins!
Title: Re: 68xxx cpu-which runs the hottest?
Post by: PMC on September 20, 2003, 12:34:22 AM
Gotta be the 68040.

The higher the clock, the hotter they run.  Don't even think of installing an '040 without a chip fan or heat sink especially if it's to be fitted in an A1200.

Oh, and '040s are very heavy on the juice too.  
Title: Re: 68xxx cpu-which runs the hottest?
Post by: Plaz on September 20, 2003, 01:51:27 AM
My 060 will burn any arse when it's clocked at 80mhz :) I have 2 small fans on it.

Plaz
Title: Re: 68xxx cpu-which runs the hottest?
Post by: iamaboringperson on September 20, 2003, 02:03:57 AM
Quote

Prmetime wrote:
I'm trying to do a little research on the 68000 series of CPUs and I'm trying to figure out which run hot, warm, or cold.  If I remember correctly, the 68030 and 68040 run pretty hot while the 000, 010, 020, and 060 run quite cool (meaning they don't require a fan).  Can anyone help me out here?

When the 040 runs at ~ 25 MHz (like on the commodore boards) it doestn't need a fan, in fact it's quite cool with just the standard thin heatsink.
Title: Re: 68xxx cpu-which runs the hottest?
Post by: amigamad on September 20, 2003, 02:46:33 AM
 68040. on my bliizard ppc runs very hot until ii fitted a 486 cpu heatsink and thermal heatsink compound.
Title: Re: 68xxx cpu-which runs the hottest?
Post by: Druideck on September 20, 2003, 07:21:11 AM

@Plaz

You say your 060 is running at 80mhz?? 66 is the
max i think.
Title: Re: 68xxx cpu-which runs the hottest?
Post by: iamaboringperson on September 20, 2003, 07:49:52 AM
Quote

Druideck wrote:

@Plaz

You say your 060 is running at 80mhz?? 66 is the
max i think.
It's called "overclocking" ;-)