[rescue] E3500 Backplane Bus Speed Question

[Dave McGuire]

On Mar 8, 2004, at 5:49 PM, Michael Thompson wrote:
> Prtdiag says that all of the boards in my E3500 are capable of running 
> with
> a 100 MHz backplane bus. The backplane bus is actually running at 84 
> MHz.
> Is this being limited by the 336 MHz CPUs?

   Yes...you need to bump up to 400MHz processors to run the bus at 
100MHz.  A 4:1 divider takes the CPU clocks and feeds the bus.

> One of the manuals says that the backplane clock speed can be set in
> firmware. Any idea how to do this?

   I've contacted to a buddy of mine on another list about it...he's a 
former Sun employee and he knows this stuff cold.  I'm waiting for his 
response on the OBP clock configuration stuff.

        -Dave

--
Dave McGuire                      "My tummy hurts now, but my soul
Cape Coral, FL                   feels a little better."     -Ed