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Unlocking core #4 on Phenom II x3 720

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I have a foxconn A79A-s. Is it possible to unlock the fourth core on a phenom II x3 720? and how would I do it?
 
Only if the motherboard has the option to unlock it in the bios. If it isn't there, your board won't do it. Even if the option is there, there's always the chance it won't unlock anyways.
 
The A7DA-S 3.0 will unlock the BE 550 to an x4. I did it, and here's the boot recipe I used:


P03 BIOS (no longer on Foxconn site, so use rogue images at your own risk)

ACC "Auto"

HT 1600 MHz

CPU voltage +150mV (will try lower - dunno what's with CPU-Z in the photos - the voltage isn't that high)


After boot, use OverDrive to tweak up. I've tried mild overclocking (16.5x on CPU) but I haven't pushed it. It's stable on the AMD stability test for an hour.

P04 and P05 BIOS appear to have the ACC core unlock feature disabled. I haven't rigorously retried these because I am so ecstatic having a 3.1GHz quad core that I haven't redone all the flashing yet.
Taken from xtremesystems
 
To unlock AMD CPUs (that can be unlocked) go to the BIOS (when you turn on computer keep pressing delete until you see some boxes with pretty red blue colour and yellow texts), and find the 'Advanced Clock Calibration' option and change it to 'Auto' (try other options if it doesn't work), usually under Overclock Settings/Advanced Settings or similar names (Can't remember what my AsRock board had).

If it goes to blue screen at any point then it's probably unstable, try increasing voltage on the CPU and north bridge (although it could be dangerous, so add little at a time and try).

Best of luck making your CPU shine even more.
 
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Well ive tried acc on auto and i tried pretty much every set of acc settings. No luck so far.
The 4th core just doesnt show up. Maybe ill try updating the bios. Thank you guys for your help.
 
Well ive had the chip running for 2 years now at 3.4 ghz so i guess i can live with 3 cores. :)
 
In other not to start a new tread with same title I will post here. Having issues when I unlock 4th core on my PII X3 720. He need a little more juice to be stable on 3GHz (0,05V), and he is perfectly stable under load. Problem is when it goes in idle state and CnC turns on. Getting some weird artifacts and sound doesn't work very well. It appears that he need little more juice in lower P states. How can I fix that, besides turning of CnC? My computer works 24/7, so any power savings are welcome... Also, is 68C (CPU) and 60C(cores) to high?
 
In other not to start a new tread with same title I will post here. Having issues when I unlock 4th core on my PII X3 720. He need a little more juice to be stable on 3GHz (0,05V), and he is perfectly stable under load. Problem is when it goes in idle state and CnC turns on. Getting some weird artifacts and sound doesn't work very well. It appears that he need little more juice in lower P states. How can I fix that, besides turning of CnC? My computer works 24/7, so any power savings are welcome... Also, is 68C (CPU) and 60C(cores) to high?

There is no setting for voltage at low power state. The 4th core is unstable. Also, 60c cores is too high.
 
So, there is no other way??? Hell.....:cool: I just live it the way it is, 3 cores on 3.4GHz...
 
You can probably try PhenomMsrTweaker to assign CPU and CPU/NB voltages to different multipliers. I use it to undervolt my mobile Phenom II X920 45w processor into a 35w one so my notebook doesn't fry.
 
I have the same chip and same mobo. No luck with the 4th core its now sitting in my htpc and the msi mobo has ACC as well. Its not a 4xcore i don't think. but iv had it hit 3.9ghz and 3.85 stable
 
Their are very slim chances that x3 will unlock. On my own 720 that came from a decent batch it still doesn't unlock.
 
The first Athlon X3 I had (455) unlocked both a core and level 3 cache. The one I have now only a core, and all I had to do was to push F4 during POST and it automagically did it by itself.
 
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