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AMD Phenom II X4 955 running at 800Mhz per core

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  • AMD
  • Motherboards
  • Phenom
Last response: in CPUs
March 24, 2012 11:24:40 AM


After an extensive test, and trying to do research on this, I found out that my good old AMD Phenom II X4 955, only runs with a clock of 800MHz instead of the promised 3.2 Ghz.

AMD OverDrive states this too.

I've used this CPU for 2 years now, so this makes me wonder. There must be some kind of hardware issue with my motherboard.

Which is a Gigabyte GA-790XTA-UD4

Reading on wikipedia I found this following:
Some top-level AM3 processors (x945 125W, x955 and x965) require a special power-supply feature, often called "dual power-plane". It's supported by default in all native AM3 mainboards, however not in most AM2+ mainboards, even those advertised as "AM3 optimised" or "AM3 ready". Processor running below its nominal speed (i.e. at 800 MHz), clock and multiplier locked are symptoms of this incompatibility. This is caused by the processor itself: when it detects that the motherboard does not supply dual power planes, the chip locks its multiplier to 4x. This issue is not resolvable via BIOS update; however, users of AM2 and AM2+ motherboards can still use Phenom II processors excluding the 125 watt variants. [11]

Does this mean, that my motherboard is incompatible with my cpu? As far as I knew, my motherboard does have an AM3 socket, and shouldn't have this issue.

Could this potentially be solved with a bios update?

Thank you for your time!

More about : amd phenom 955 running 800mhz core

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March 24, 2012 11:34:01 AM

it can be solved by going into bios and turning off cool and quiet, it throttles the cpu down to 800MHz (200x4 multiplier) when not needed, saving heat and lowering your bill
try using coretemp and watch the core speeds change when you start a virus scan (for example),
it will go up to the needed speed (max 3.2GHz on stock settings)
there is no problem, don;t worry :) 
March 24, 2012 11:37:22 AM

Oh alright, thank you! I did start to worry quite a bit :) 
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March 24, 2012 1:11:35 PM

No problem,its quite a common 'problem' here and on other forums, :) 
March 24, 2012 1:24:04 PM

So if I disable the cool and quiet, then 3DMark should be clocking other speeds?
March 24, 2012 1:47:47 PM

No, cool n quiet means that it clocks down when they're nothing for it to do. When it is under load (3DMark) it clocks up. Run 3D mark/prime and look at your speed while its running.
March 24, 2012 2:22:10 PM

Oh right, I can see that yeah. Thank you for the reply! It solved a lot of future nights without sleep ;D
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March 24, 2012 5:29:58 PM

Sleep is overrated anyway :)