There arn't much of a risk involved. Clock caliberation is primarily built for better ocing in which u can set the tolerence level manually for each cores. It means, CPu wont hang up with the error being lower than the tolerence value we have set.
So the disabled cores, which migh have some erros or just masked get activated, provided the error ratio is lower than the tolerance.
We casn set tolerence from -12 to +12%.
Practically AMD makes all CPUs together, i mean the Phenom IIs. They checks the workability of the cpus, each cores individually. Those with one or two cores having slight higher error are made X2 or X3 by locking the cores.
But to meed the market demand, they lock cores of fully functional x4 cpus too and sell as X2 and X3. Good batches means, they have fully functional cores at heart. If u are lucky to find such batch, dont wait and enable ACC, and try Auto, and if not successful, go up the value to 12% max.
You will have to reset bios many times in the procedure, but dont worry, u not gonna fry nythin.
please dont quote this, as i am not exactly sure bout the working of this ACC thing:bleh:
And one more thing. The unlocking is temporary, ie just for that boot. If you reset the bios or turned ACC off on next boot, it ll back to x2 or X3. Same is tha case if you change the mobo to some 780 or 760/740 later. And unlocked proccy cud heat up more easily than the stock ones. So keep an eye on 8it, and most probably unlocked cores will fail to address temps. Use manual methods by some temp sensing chips or make sure its running cool by6 attaching good cooler and maintaining good airflow in chassis.
@bs0409
btw, the unlockable batch of x2 550 is now in stock with amarbir. i have ordered one.

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ill be getting an X2 550 0922apmw in a day or two, which has 99% probability of unlocking. Will try different settings and will inform you guys.
will try to log the temps using an external sensor touching the heatsink part close to the CPU-heatsink junction. Many reviews says the unlocked PII runs pretty hot on stock cooler. Will check that.
