Overclocking the Motorola 860 family
Hello,
Has anybody overclocked a MPC860 or a MPC850? Motorola says
they top out at 80 Mhz I was wondering if anybody has successfully cranked these babies up near 100MHz. Right now we run our 850 at 49.1MHz and I want to double it. I was hoping to find out if how much of a performance bottle neck was I/O based and processor speed based without having to rework my UPM SDRAM code.
Thanks
Conn
--
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If you live at home long enough, your parents will move out.
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Conn Clark
Engineering Stooge [email protected]
Electronic Systems Technology Inc. www.esteem.com
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Quoted 1 line · Conn Clark
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....
Quoted 2 lines
.... 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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