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Zetr0 · 22 March 2011, 09:56

@Cosmos

According to the data sheet I have on the Motorola 68060 family CPU, Section 12: Electrical and Mechanical Characteristics > Page 343

Under normal operation of 3.465 volts the following power dissipation pattern

50MHz = output 3.9Watts = 1.126 Amps
60MHz = output 4.9Watts = 1.414 Amps

That is a factor of 0.288 Amps dissipation for a 10Mhz increase, what that is internally I am not 100% sure but I suspect it would be very close to those numbers.

Since we are altering the voltage (volume) of the electrical input, it will offset the needed amps (current) required to push the gates - thus -

if you increase the voltage between 3.6 - 3.8 volts with a maximum draw of 1.8 Amps you should be able to have a stable 060 at 90Mhz... (3.7v / 6.9Wd = 1.86 Amps)

But that's only half of one possible solution.. like the timing of an engine in a car if only one part is slightly off-beat then its just going to hang... calculating the right frequency so that everything is in step - that's all the logic, both in propagation and process delays, also the RAM timings, is very important.

I find writing it out on paper with a calculator is actually quicker than trying to plug at it on notepad++ as you soon see the patterns needed. That's why there are some non-working frequencies with the Amiga, where although the CPU can run, the rest is just out of step.

you can find the timings in both the A1200 schematics and you can find the CPU timings in the Motorola specification sheet on Section 7: Bus Operation - page 156,157 etc.

As you know my friend, the choice of RAM is very critical too... I would suggest that if you go above 66Mhz think about getting 50ns RAM - yes.... its rare, but these are going to get hammered and I have 60ns memory that fails even at 66Mhz.

I have only 1 stick of 32MB at 60ns that will run on my Apollo 060@80Mhz, unfortunately the last time I held 50ns RAM was a fair few years ago!

22 March 2011, 09:56	#13
Zetr0 Ya' like it Retr0? Join Date: Jul 2005 Location: United Kingdom Age: 49 Posts: 9,768	@Cosmos According to the data sheet I have on the Motorola 68060 family CPU, Section 12: Electrical and Mechanical Characteristics > Page 343 Under normal operation of 3.465 volts the following power dissipation pattern 50MHz = output 3.9Watts = 1.126 Amps 60MHz = output 4.9Watts = 1.414 Amps That is a factor of 0.288 Amps dissipation for a 10Mhz increase, what that is internally I am not 100% sure but I suspect it would be very close to those numbers. Since we are altering the voltage (volume) of the electrical input, it will offset the needed amps (current) required to push the gates - thus - if you increase the voltage between 3.6 - 3.8 volts with a maximum draw of 1.8 Amps you should be able to have a stable 060 at 90Mhz... (3.7v / 6.9Wd = 1.86 Amps) But that's only half of one possible solution.. like the timing of an engine in a car if only one part is slightly off-beat then its just going to hang... calculating the right frequency so that everything is in step - that's all the logic, both in propagation and process delays, also the RAM timings, is very important. I find writing it out on paper with a calculator is actually quicker than trying to plug at it on notepad++ as you soon see the patterns needed. That's why there are some non-working frequencies with the Amiga, where although the CPU can run, the rest is just out of step. you can find the timings in both the A1200 schematics and you can find the CPU timings in the Motorola specification sheet on Section 7: Bus Operation - page 156,157 etc. As you know my friend, the choice of RAM is very critical too... I would suggest that if you go above 66Mhz think about getting 50ns RAM - yes.... its rare, but these are going to get hammered and I have 60ns memory that fails even at 66Mhz. I have only 1 stick of 32MB at 60ns that will run on my Apollo 060@80Mhz, unfortunately the last time I held 50ns RAM was a fair few years ago!