There is also quite a bit of information on Mac clock-chipping at 
http://violet.berkeley.edu/~schrier/mhz.html.

Apparently, several people have investigated putting faster clocks into 
SE/30s. The unanimous conclusion seems to be that the cpu clock in a 
stock SE/30 is shared at least with the video card, and as I recall, 
everything. At the minimum, if you changed the clock, your monitor would 
be useless.

I have a 40MHz Daystar accellerator (slotless) in my SE/30. This card 
also came in a 50MHz variant. I tried changing the clock on the 
accellerator card itself via one of the jumpering mechanisms recommended 
at the URL above. I couldn't get the machine to boot at 50MHz at all. I'm 
assuming/hoping that it's just that my CPU and FPU can't handle 50MHz 
(they're only rated at 40). I haven't been able to find a faster CPU to 
see if it would make a difference (haven't tried really). I also haven't 
been able to get a hold of any slower clocks to see if I can at least eek 
a few more MHz out of it. To be honest, I haven't even tried a jumpered 
40MHz clock to confirm that my jumper worked.

So, no success stories here, but the theorey is still sound 8-)

This accellerator even came in 33MHz variants. If you can find one, you 
should be able to up it to 50MHz with your CPU and a little clock 
chipping on the Daystar card!

-1LT Avram Dorfman
HQ USAF Network Management
permanent email address: avram@pobox.com

"Methodological observation of the sociometrical behavior tendencies of 
prematurated isolates indicates that a causal relationship exists between 
groundward tropism and lachrimatory behavior forms."

On Fri, 7 Jun 1996, Ben Hockenhull wrote:

> I have an old Apollo 400t that I'm upgrading to a 425t via motherboard
> swap.  The 400t board has a socketed Motorola 68030 chip that runs at
> 50mhz.
> Hmmm....I thought, Maybe I can put that cpu in my SE/30 which runs MacBSD...
> S
> So, my question is, can anyone think of a reason why I would not want to do
> this?  I assume that since its an 030 chip, just faster, there shouldn't be
> any problems but wanted to make certain before going ahead.  It sounds to
> me a lot like putting in a DayStar 50mhz accellerated chip.  Am I
> overlooking anything glaringly obvious here?
> 
> Thanks.
> 
> Ben
> 
>