Re: Overclocking the Motorola 860 family

Conn Clark wrote:

	Has anybody overclocked a MPC860 or a MPC850?

I've tried cranking up the PLLs beyond the chip spec.  None of them
have ever worked.  I could only get 4 MHz steps, so I tried the 80 MHz
at 84MHz, which didn't work (including all UPM timing changes to ensure
memory was OK).  Maybe it would run at 81 or 82 MHz....

.... Right now we run our 850 at
49.1MHz and I want to double it.

No way.  I've tried lots of different speed spec parts at higher than
rated values, none has ever worked for me.  It appears Motorola has a
pretty good screening process, and when they state 50 MHz it isn't likely
to run beyond that.  Even if one appears to work, I wouldn't expect a
product or volume manufacturing to be successful.


	-- Dan


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