I bought a 68060 revision 6 (71E41J) recently for a very good price. The rev. 6 CPU can usually do a really good overclock, often reaching 100MHz or more, which makes them very sought after and sometimes fakes are offered as the genuine version of the CPU. As I was already running an 060 in my Amiga 1200 I was not sure if it was worth swapping CPUs to gain more megaherts. The rev. 5 68060 I was running could do a 66MHz overclock but ran very hot. And a 50MHz 060 is not a slow CPU (in the world of Amiga).
Swapping 68060 CPUs in my Amiga 1200
I decided to swap CPUs because I wanted to test performance of an Amiga without a graphics card but with a fast CPU and high resolutions (like HighGFX and highres laced). Luckily removing the CPU was not a difficult task, prying on the corners of the socket it was out in less than 5 minutes ready to go into another one of my systems. Once the rev. 6 CPU was inserted into the Terrible Fire 1260 I was eager to do a test. Sure enough, it did not complain anything running at 100MHz!! (keep in mind I had a heatsink on the CPU when doing tests). Next time I will try 106MHz!!
Is there actually a noticeable difference between a 50 and a 100 MHz 68060?
Would I be able to detect any difference between a 50MHz 060 and a 100MHz 060 or would it only be noticeable in a benchmark program?
I was not too sure – When I had overclocked my 060 in my Amiga 4000TX from 50 to 100MHz I could feel that icons loaded faster, drawers just popped up, Workbench was just smoother and more responsive. But I was not sure if it was my imagination or reality.
With that said, I was surprised that my 100% non scientific mean of measuring the difference between a 50 and a 100MHz CPU in the following AGA Amiga Workbench screenmodes highres, highres laced, HighGFX @ 1024×768 (all screen modes in 64 colors) proved that there really was a difference!
Workbench had become even faster and more responsive. Running 3.1 with the stock Commodore 4 color icons, icons did not load anymore, they just popped up, almost all at once, drawers opened up instantly. The system speed by at such a high rate I had only witnessed something like this in WinUAE. What an amazing experience!
I changed background colors to 256 colors and could sense little to no slowdown from a 64 color screenmode. Sure, I have to test this more, but the early results are great, this is what base level Amiga should be like! Lets bring on 200MHz 060 (lets crowd fund it lol).
Cooling problems
Before I permanently run this computer at 100MHz I have to figure out a good cooling solution for the CPU. This rev.6 68060 runs cooler than the old rev. 5 I had in it before. But overclocking it makes it run slightly hotter. I suspect its above 50 degrees but not more than 60. I have some ideas on how to cool it down but will have to sleep on the ideas a little more before I pull the trigger on the stuff I need to build one..