On Fri, 10 May 1996 16:22:53 +0200, A.Arnold wrote:
>2. The 3/60 has an option to plug in a 68030 instead of the original 68020
>   CPU.  I soldered in the required socket and did the replacement.  The system
>   still works fine, but without any speed improvement.

You won't be able to get any improvement, because the cache doesn't work
with Sun's custom VM hardware. The only improvement would be that in a
few places a new/changed 68030 instruction would be a little more efficient,
but that won't be very noticeable: most instructions are exactly the same
speed as the 68020.

You can improve speed by using a 25 MHz 68030 and changing the clock.
Since the Sun uses different clocks for various pieces of the board,
it's possible to get a working system at this speed. The Sun-3 archive
has more info about this. The URL http://wwwedu.cs.utwente.nl/~boschg/Sun
contains links to this info.

Regards,
   Geert
---
E-Mail: geert@sun3.iaf.nl 
 Phone: +31-53-4303054