OverClocking my 867mhz QS...help please

8thDegreeSavage

macrumors 6502
Original poster
Jun 5, 2002
370
0
Toronto, Ontario, Canada
All i need is some indepth info on how this is done..preferably via a software OC if possible...but a hardware OC is fine as well...i have heard of people OCing 867 to 1GHZ stable....


Any sites or info would be great....
 

vniow

macrumors G4
Jul 18, 2002
10,281
0
I accidentally my whole location.
found this from a link on MR awhile ago, don't remember where

Edit:Here's the link.




The following are instructions to use OpenFirmware to overclock the
Front Side Bus of Apple's new Dual 867 Power Mac from 133 Mhz to 167
mhz. This overclock will also indirectly overclock your CPU's from 867
Mhz to 1083 Mhz.

NOTE: All <return>'s are places where you are to push the return key.

1. Boot into OpenFirmware ("Command-Option-O-F") and at the prompt enter the NRVRAM editor.

nvedit<return>

2. Line by line enter in the script just as it appears here including the spaces.

" /" select-dev<return>
09ef21aa " clock-frequency" get-my-property 2drop !<return>
" /cpus/PowerPC,G4@0" select-dev<return>
09ef21aa " bus-frequency" get-my-property 2drop !<return>
408e4b46 " clock-frequency" get-my-property 2drop !<return>
09ee81bc " config-bus-frequency" get-my-property 2drop !<return>
027ba06f " timebase-frequency" get-my-property 2drop !<return>
" /cpus/PowerPC,G4@1" select-dev<return>
09ef21aa " bus-frequency" get-my-property 2drop !<return>
408e4b46 " clock-frequency" get-my-property 2drop !<return>
09ee81bc " config-bus-frequency" get-my-property 2drop !<return>
027ba06f " timebase-frequency" get-my-property 2drop !<return>

3. Exit the NVRAM editor by pressing "Control-C".

4. Save the script to the NVRAM.

nvstore<return>

5. Tell the OpenFirmware to enable the use of NVRAM startup scripts.

setenv use-nvramrc? true<return>

6. Tell the OpenFirmware to save and restart your computer.

reset-all


That's it. Pretty easy, and the best part is that it doesn't require any soldering.

KNOWN ISSUES:

Some utilities don't accurately report the speeds of the FSB and the
CPU's. For instance Apple System Profiler reports that the CPU's are
running at 1.83 Ghz instead of the proper 1.083 Ghz. And I have not
found a program yet that can properly determine that the FSB is actually
running at 167 Mhz.

I'm going to try and figure out why this is, but my first assumption is
that it's because this script doesn't overwrite the values stored in ROM
it just overrides them with values stored in NVRAM. Since most programs
only probe directly to the device tree ROM information they won't see
the values stored in NVRAM. Programs which try to actively calculate
the CPU's speed and FSB speed will probably provide a more accurate
figure than programs which just probe for information in ROM. Also bear
in mind that for best results you'll probably have to replace the PC2100
DDR memory in your machine with PC2700 DDR memory as the former is
designed to operate only at the stock 266 Mhz, whereas the latter is
designed to work at the new speed of 333 Mhz.



WARNING:

I'm pretty sure that this will void your warranty. The upshot is that
if you ever want to undo the overclock and get back to factory settings
all you have to do is reset your PRAM by holding "Command-Option-P-R"
at startup. Which will then leave no trace that you've ever performed
this operation.

***USE THIS AT YOUR OWN RISK!!!*** It's possible to render your CPU's
and/or RAM unusable by overclocking them beyond their designed
specifications. It's also possible to render your machine unusable by
altering the OpenFirmware in irrecoverable ways. Though I have had
success and have not experienced failure induced by this OpenFirmware
script I am not going to be liable to others who use this.
 

Hemingray

macrumors 68030
Jan 9, 2002
2,913
25
Ha ha haaa!
Re: found this from a link on MR awhile ago, don't remember where

Originally posted by edvniow
The following are instructions to use OpenFirmware to overclock the
Front Side Bus of Apple's new Dual 867 Power Mac from 133 Mhz to 167
mhz. This overclock will also indirectly overclock your CPU's from 867
Mhz to 1083 Mhz.
From the sounds of it 8thDegreeSavage is talking about the single processor 867 QS, not the new dual 867 MDD.

And BTW, here's the overclocking information page:

http://www.bekkoame.ne.jp/~t-imai/g4de1.html
 

Sun Baked

macrumors G5
May 19, 2002
14,874
57
Originally posted by edvniow
Yeah, I see it now. QS, not MDD. Goddammit, this is the second time I've done this, maybe I should read the entire post before I start spamming.:eek:
If you do that, it wouldn't be spam...

Which would deprive the world of a potential Spam® Burger.
 

8thDegreeSavage

macrumors 6502
Original poster
Jun 5, 2002
370
0
Toronto, Ontario, Canada
Thanks for all the input so far guys...and yeah im talking about the single pro 867.


I have seen that Japanese page before...it doesnt offer much info...i need some info on this, like an article by someone who has done it.
 

ryme4reson

macrumors 6502
Mar 5, 2002
259
0
Cupertino CA
Thanks but..

Is there possibly a software method? Thanks. I am not comfortable soldering my computer. Also, if my mom walks with with me, my computer, and a soldering iron she will have a fit. Atleast typing she cant blame me for anything that goes wrong.

"I was solding the CPU card and now it doesnt work, can you get me a new PowerMac, and hurry I need it for school" -- Not gonna fly.

"I dont know what happened, but I need a new comp as soon as possible, ley go to the Apple store tomorrow!" -- possible
 

MacBandit

macrumors 604
Re: found this from a link on MR awhile ago, don't remember where

Originally posted by edvniow
Edit:Here's the link.

The following are instructions to use OpenFirmware to overclock the
Front Side Bus of Apple's new Dual 867 Power Mac from 133 Mhz to 167
mhz. This overclock will also indirectly overclock your CPU's from 867
Mhz to 1083 Mhz.

That's very intersting because www.xlr8yourmac.com posted today a link to a page showing how to change the resistor values to change the bus speed from 133 to 167. So that would mean that it's both software and hardware or maybe you need to change both.

Here's the link to the page with the hardware fix.

http://translate.google.com/translate?u=http://www.macbidouille.com/niouzcontenu.php?date=2002-10-08#3610+&langpair=fr|en&hl=en&ie=ISO-8859-1&prev=/language_tools


Oh, and one more thing I just thought of. The reason it is not displaying correctly is quite possibly you haven't changed out your PC2100 ram for PC2700 ram necessary for running the bus at 167Mhz.