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AMD Phenom II X4: 45nm Benchmarked

Only 800 MHz and 0.992 V When Idle

As with its predecessor, the Phenom II comes equipped with AMD’s Cool’n’Quiet energy saving functions, so that when the processor finds itself idle, it can lower its clock rate and core voltages. In conjunction with the motherboard, the processor can even turn off unneeded voltage regulators. A first-generation Phenom can lower its clock rate to a minimum of 1,250 MHz because the smallest possible multiplier is set at 6.25.

In contrast, the Phenom 2 can drop its clock rate to a mere 800 MHz thanks to a minimum multiplier of 4.0. The 45 nm technology enables the core voltage to be dropped from 1.040 V to 0.992 V. AMD has been generous in the voltage range it permits for the Phenom II--the chip’s technical documents define operating ranges from as low as 0.875 V and as high as 1.5 V. This might mean that some processors do better or worse than others in terms of power savings. Another clock reduction at idle depends on the architecture and the production process. Stable operation of the processor at very low clock rates depends as much on capacitance and inductance in the system as it does on the switching rate of the transistors in use. This can sometimes entail a complete reworking of system structure before lower clock rates become usable.

The Phenom X4 9950 Black Edition lowers its clock rate to the same 1,250 MHz and lowers its voltage to 1.040 volts as well.

At idle, the Phenom II is more energy efficient, at 800 MHz and 0.992 volts.

  • one-shot
    YAY!, The day has come! Haven't read it yet. I am excited to see what it brings!
    Reply
  • firedogevan
    why focus on the q6600... wouldn't the q9550 or 9650 be a more accurate comparison given their respective locations in the product lineup?
    Reply
  • dechy
    Yeah, the price comparison table should of included a Q9550, which costs same as i7 920 but with the lower mobo/ram combo price.

    Ends up being the same price as the AMD bundle, but with a good more performance... there goes the whole "AMD price/performance" aspect of this chip.
    Reply
  • one-shot
    Great review. Maybe some overclocking later? There were some pretty high claims about its overclocking potential. I'll wait for AM3 before I retire my E6750.
    Reply
  • cangelini
    Coming up soon one-shot--I was working on that one =)
    Reply
  • V3NOM
    who cares about performance/watt? PRICE/PERFORMANCE is the big deal
    Reply
  • The Q9xxx series would trump the PhenomII in all the categories listed above. THG, it was downright *criminal* to have not included the Yorkfield chips in your performance per dollar and performance per watt analysis.
    Reply
  • nashville
    hey bert/tom's:
    good write up: thought id comment on i7 watts:
    "we measured the power consumption directly from the 12 volt rail that supplied the CPU", i read somewhere the only i7 core logic gets power from 12v rail, the uncore/cache part somewhere else. if this is true, you going to do another measurements?
    Reply
  • kirvinb
    I'm so happy to see Intel has some competetion. While these new processors are not mind blowing, they offer some decent performance at the price given. I am sure this will lower the price of the q9400 and q9550, which is exactly what I want to see. Maybe even the i7s price will lower and maybe we will be back in the good days..where intel and amd flipped sides of the powerhouse like every 6 months..!! Good Write Up..
    Reply
  • jj463rd
    On the forums someone mentioned "why did they use DDR2-800 RAM when DDR2-1066 would give better performance for the Phenom II".Wouldn't this skew the benchmarks by a little bit (perhaps 2 to 3%)?
    Reply