Area: Aminet/hard/hack
Short:  Convert Stock a3000-25 to run at 33mhz



Well,
	I was wanting more speed on my a3000 since 25mhz was only
half as fast on AIBB as my g-force 030 40mhz was on my a2000.
After reading about about an FPU hack (it double the fpu clock) I
started checking out all the 33mhz a4000 hacks.  I did some
checking with some people, and found that the FPU clock double
worked and the a4000 hacks worked also.  I ran the 50mhz FPU for
2 months and decided I wanted to try running the CPU faster.
Everyone told me that I could only run at 28mhz safely, but I
checked and a few people said 33mhz was safe.

	I found I could run most chips on a 16 mhz board safely
at 25, so I figured they could handle 33mhz with few problems.
I also found that I could run a 16mhz a3000 at 25mhz, so
hopefully no problems with 33 on a 25.  One problem, according to
the FPU hack, my 25mhz 68882 can only run at 50mhz, so I had to
remove that hack (which took a while.)  Once this was removed no
problems should arise.

66mhz clock(full size)........Digi-Key part #CTX137-ND US $5.00
14 pin MG Socket .............Digi-Key part #AE7214-ND US $0.85
Heat sink.....................Digi-Key part #HS178-ND  US $4.18
        (If you want, just pick this up at your nearest PC Dealer)

INSTALLATION:  Once you have ordered these parts, just solder the
socket where the 50mhz crystal was, and place the 66mhz crystal
in it.  Now put the heatsink on the 68030.

Although this doesn't require the heatsink, it will sure extend
the life of your CPU (You should have one on there anyway!)

Now: Software, BEFORE you install the 66mhz crystal, you MUST
CHANGE YOUR S:STARTUP-SEQUENCE.  Modify the line

SETPATCH QUIET (As the commodore startup-sequence has it)

change it to:

SETPATCH NOCACHE
CPU CACHE NOBURST

REASON: It seems that pre-rev 11 busters don't like 33mhz in burst mode.
However, if you have the rev-11 Buster, you should be able to
change it back to burst mode.

NOTE: do not buy the cheap radio shack 14pin socket.. If you want
to change back to 50mhz, the original crystal won't fit the
cheap radio chack socket, that is why you should get the machine
grade socket.

FPU NOTE:  make sure you have removed the 50mhz FPU hack if you
have it installed, changing the crystal to 66mhz would change the
FPU to 66mhz and then fry the FPU.

PLEASE NOTE: in case you are curious, I have:
REtina Z3 4M,
dkb3128 w/ 12M
Oktagon 2008 w/ 4M w/ 1gig micropolis
all these run fine together

ALSO NOTE:  this project is at your own risk.  Don't blame me if
you fry your machine due to incompetence, it has been working
fine on my machine for a while now, up to 9 hours continuously
with no problems.  (I shut it off when I am not using it)

PS:  I included the a4000-33mhz hack from aminet, just in case you wanted
to read it from someone else, although I did not write it, this text is my
own project, and I have plagiarized(sp) no one.

Magazines, Fred Fish, Aminet:  Please feel free to use this archive in any
thing you wish, if it goes in a magazine or on a CD please send me a copy
however.  Thanks you!

Original Upload Site: Dawn of Eternity BBS 7-5-95
Author: Charles Steffes-Clayton
Other programs by author:
	ECSDiagnosis -- program to diagnose ECS machine problems