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Tuxedo Man
Mar 26, 2009, 09:43 PM
Has anyone ever successfully overclocked the PowerPC 7450 v2.0 all the way up to 1.07 GHz (1066 MHz)? Right now I have mine at 867 MHz and it was originally running at 733 MHz. It runs totally fine at 867 MHz. I was wondering if I could get it up there without causing the transistors to burn.:confused:



Hrududu
Mar 26, 2009, 10:18 PM
Has anyone ever successfully overclocked the PowerPC 7450 v2.0 all the way up to 1.07 GHz (1066 MHz)? Right now I have mine at 867 MHz and it was originally running at 733 MHz. It runs totally fine at 867 MHz. I was wondering if I could get it up there without causing the transistors to burn.:confused:
I know more than 50MHz was tough to get on a G3. I'm really not sure about G4 Powermacs, but I know getting a 1.25GHz Mini would run great at 1.33 and the 1.42 at 1.5GHz. I'm gonna guess that 300MHz might be pushing it a bit much.

aibo
Mar 26, 2009, 11:37 PM
You won't get it to clock that high. Even if you try, you won't "burn" or damage anything. The machine simply won't boot. The only G4 that was any good for overclocking was the 7455B.

SmurfBoxMasta
Mar 27, 2009, 06:03 AM
oveclocking by 300mhz is probably a stretch for most chips......the fact that you got it up by 133 does NOT mean it will tolerate over 2x more than that.....at least not without some serious voltage mods & extra cooling....

Back when I had a B&W G3/350, I got it to run @500 nottaproblemo, just by moving the jumpers. Then later I upgraded it to a G4/500, and got it to run at 600, but as soon as I tried 650, it would NOT even chime, let alone boot up :p

Tuxedo Man
Mar 27, 2009, 03:20 PM
You were able to get a 500 MHz up to 600? Was this a PowerPC 7400? I got a 450 MHz 7400 v2.8 to run at 500 MHz but I could never get any further. I didn't think it was possible for a 7400 to run any faster than 500 MHz. I got my 7450 up to 1.07 GHz and it chimed when it started up but continued to show a blank screen for a while. So I successfully down-clocked it back to 867 MHz and it's working fine. One more question, I looked into it more and I guess some people clocked a 733 MHz 7450 up to 933 MHz successfully. But in order to do that I would have to remove the last remaining resistor on the processor and replace it with a solder trace. Would it overheat if I took off the resistor and ran the processor just using solder traces. I couldn't possibly remove the resistor and then re-solder it back on.

aibo
Mar 27, 2009, 04:17 PM
There were a bunch of of 500MHz rated 7410's clocked up to 600MHz and sold by FastMac and OWC. I had one in my G4 Yikes -- ran it at 650MHz. 700MHz ran too (http://db.xbench.com/merge.xhtml?doc1=70879), but turned out not to be stable over extended periods. I think I'm the only one to run @ 700MHz in that machine while keeping a 100MHz system bus.

The 7455B was very good for overclocking. The highest it came rated was at 1.25GHz but it was sold "guaranteed" at 1.467Ghz and 1.5GHz speeds by various places, including OWC and GigaDesigns.

I had a 1.2GHz rated GigaDesigns 7455A "guaranteed" at 1.33GHz which it ran beautifully at. I tried it at 1.4GHz and 1.46GHz but it would not boot, not even with a voltage boost.

Dave H
Mar 27, 2009, 06:47 PM
The 7455B was very good for overclocking. The highest it came rated was at 1.25GHz

They went up to 1.4GHz rated.
Mine is rated 1333MHz, as stamped on the actual chip.