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Nameci

macrumors 68000
Original poster
Oct 29, 2010
1,944
13
The Philippines...
I recently bought a PowerMac G4 1.42GHz Dual Processor. It has 2 gigs of RAM on it. It was a fair deal I think. The "thing" is still looking like new and shiny. Even the insides are still tidy and intact.

My question is, would I still be able to pump more juice from this beast. It still run fast comparable to some decent windoze box. Up to how much processor can i be able to squeeze out the CPU and if possible, how to?
 
1.5 GHz is pretty much a given without any changes to core voltage. Also, this can be done by only removing resistors (you don't have to solder anything).

Beyond this, it's hit or miss. Not all CPU's, even with the same rating, will be the same. Some folks get them running fine at 1.67GHz while others have had trouble at 1.58 GHz. 1.67 requires upping core voltage, which introduces more heat. 1.58 usually requires this too, but I think I've seen one or two reports of people running 1.58 at stock voltage (I've never been able to).

If you up the voltage, I strongly recommend additional cooling.

Settings: http://bitsandpieces.info/Multipliers.htm
 
I might not as well do it, 1.42 to 1.5 is not that much of a bump. If it will make the system not stable at 1.67 then I'd rather not compromise the systems stability over speed.
 
You never know until you try. As long as you're comfortable with your soldering skills you can always drop it back down if it isn't stable. :)

I feel you, though. I tend to err on the side of having cooler running machines.
 
I have a good soldering skill, i work in an equipment servicing field. I just don't feel the urge to overclock it if I only gain around 100MHz on my CPU speed... I just ask if it is really safe and stable and proven to be stable...
 
it can be done stable to 1.5 ghz , but you wont notice the difference really , so in my opinion not worth the afford for 80mhz more ,

better invest for performance improvement in a better graphics card if you feel the need for a performance boost , normal in the dp 1.42 there is the ATI 9000 Pro with 64MB vram not a bad card , but a good upgrade card is the ATI Radeon 9700 Pro with 128 MB vram (if it did not came already with it , as the dp 1.42 could be ordered with the 9700pro) which brings a performance boost , and more noticeable then even 200mhz more when it comes to for example movies photoshop or such things which are graphic intense
 
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There's many reports about stable 1.58 GHz as well. I have stable 1.42@1.67DP - but it requires massive cooling improvement - only WC can handle it.

One thing you need to know about G4: you're OC'ing not only CPU, but its cache too. It's more performance gain than it looks from MHz increase.
 
yes its possible to gain performace with OC'ing but in my opinion it only makes sense after everything else is upgraded to the limit , means RAM and the GPU , and the harddrive (ssd or 10000rpm but sata card needed )
 
^ This is rather obvious. Even more: if you're satisfied with performance of your stock clocked CPU, there's no need to OC/upgrade it :) Unless you're me, for example (I'm OC'ing everything I can, even done a Indigo Clamshell last time) :D
 
i am happy with the performance of my quicksilver, could not be better i suppose , spec's dual 1.6 G4 freescale 7447a , sata card , 10000rpm velociraptor (300GB the old one ) 1.5 gb ram , ati 9700 pro 128mb , flies with osx tiger
and happily keeps up with my iMac core duo 1.8
 
Congrats, it's powerful upgrade (this 7447a DP). I'm sure you're happy with it :)

But, if it would be mine, one thought wouldn't let me sleep: "Is it able to go @1.87 or maybe 2 GHz?" ;) :p :D
 
Congrats, it's powerful upgrade (this 7447a DP). I'm sure you're happy with it :)

But, if it would be mine, one thought wouldn't let me sleep: "Is it able to go @1.87 or maybe 2 GHz?" ;) :p :D

yes i believe it could go to without trouble if i would try , but there must be a reason why freescale didn't try it too and instead went on to the 7448 1.8 and 2.0 which will even outperform with ease a intel iMac core duo with more then the 1.8ghz

but you should see tiger fly with dual 1.6ghz , and OS9 is already beyond warp factor 9 :D
damn OS9 is a real good operating system if let lose on a fast G4 Mac , i believe it would have had more potential then OSX :(
 
I am back to Tiger on my dual 1.42GHz, I find it sluggish with Leopard. This old thing flies with Tiger. OS memory footprint is really small compared to Tiger.

If OS9 only have multi-tasking... :(
 
1.67 in a G4 MDD 1.42?

There's many reports about stable 1.58 GHz as well. I have stable 1.42@1.67DP - but it requires massive cooling improvement - only WC can handle it.

One thing you need to know about G4: you're OC'ing not only CPU, but its cache too. It's more performance gain than it looks from MHz increase.

My appologies, I know this is an old thread but... could you please let me know (in detail) how you did this? I am extremely interested. I have an identical machine and would love to to overclock it to a dual 1.67.
 
There was site named bitsandpieces.info, which is currently down and I doubt that it will be ever back online. Unfortunately it was only site containing complete info about overclocking dual MDD daughtercards. Mutlipliers tables, pictures of PLL and Vid resistors location. I have most of this archived somewhere and I'll try to find pics and tables to put together such guide in nearest future.
 
There was site named bitsandpieces.info, which is currently down and I doubt that it will be ever back online. Unfortunately it was only site containing complete info about overclocking dual MDD daughtercards. Mutlipliers tables, pictures of PLL and Vid resistors location. I have most of this archived somewhere and I'll try to find pics and tables to put together such guide in nearest future.

I believe this is what you are looking for.
 
I believe this is what you are looking for.

Thank you for the link. It looks as though it's a guide for overclocking to just 1.5ghz. Is there by chance a guide for going any higher? I was hoping to achieve a 1.67ghz for my 1.42 DP.

Thanks again, it's much appreciated.
 
Thank you for the link. It looks as though it's a guide for overclocking to just 1.5ghz. Is there by chance a guide for going any higher? I was hoping to achieve a 1.67ghz for my 1.42 DP.

Thanks again, it's much appreciated.

I have absolutely no idea. I just knew that 666sheep was referring to a dead page, so I went out and found it. I am not very knowledgeable on G4 Power Macs, having never owned one. I think you'll have to wait for 666sheep's reply.
 
I believe this is what you are looking for.

Yep, but when I was trying to recover it using Wayback machine, it (strangely) didn't appear with all pictures. Thanks a bunch.


JRuss: check table. First row after yellow marking shows 1667 cpu speed with 167 bus. And this you need to set on your CPU daugtercard. Next thing is Core Voltage. Most of 1.42 CPUs won't go higher than 1.58 without CV bump. Check what voltage regulator your card has, then adjust voltage until your CPU won't be stable. Mine needed 1.75V what caused overheating with stock cooling. It was stable only using watercooling or running CPU fan at full speed.

I cannot recommend 1.67 GHz for other than testing purposes. Atlhough 1.58 is fully stable on stock cooler using Chud wit NAP enabled.
 
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