Which of these 3 CPU's will give lowest idle watt on a 780G?

Thomas · Post by **Thomas** » Mon Jun 08, 2009 5:17 am

I consider one of these 3 Phenom II CPU's:

810 X4 4 MB
720 X3 6 MB
940 X4 6 MB

Which of these will give me the lowest wattage @ idle on my Gigabyte GA-MA78G-DS3H rev. 1 board?

I'll use Q'n'Q.

Also, will these 3 CPU's give a higher idle wattage, than my 4850e? From time to time, I see comments about AM3 CPU's in a AM2+ board, results in high idle power. So I tend to stick with the 940.

The CPU is primarily for one specific use: Nikon NX2, which I havent been able to find any benchmarks on. But if Adobe CS3 benchmarks are somewhat comparable, all 3 will give a significant boost, compared to my 4850e.

Post by **MikeC** » Mon Jun 08, 2009 7:55 am

940 is 125w tdp, so I'd avoid it. The others are both 2.6GHz, 95w tdp; if CnQ works as it should, they should idle about the same. Probably worth checking around the web for specific reviews/comparisons.

dhanson865 · Post by **dhanson865** » Mon Jun 08, 2009 3:49 pm

Of the three you listed I'd get the X3 720 as it is the best bang for the buck but if you want low idle power you should consider these:

AMD Phenom II X4 905e 2.5GHz 65W
AMD Phenom II X3 705e 2.5GHz 65W

They would idle even lower per the C&Q voltages:

Phenom II X4 940 1.15V
Phenom II X4 810 1.15V
Phenom II X3 720 1.15V

Phenom II X4 905e 0.825V
Phenom II X3 705e 0.80V

Lower voltage is the primary driver for lowest overall power draw when comparing two processors.

And to add icing on the cake the x05e phenoms have lower voltage at full load also.

data pulled from http://en.wikipedia.org/wiki/List_of_AM ... processors and I did peek at http://www.anandtech.com/cpuchipsets/sh ... spx?i=3572 just to remind myself the model names to look for on Wikipedia.

Thomas · Post by **Thomas** » Tue Jun 09, 2009 10:12 am

dhanson865 wrote:Phenom II X4 905e 0.825V
Phenom II X3 705e 0.80V

Thanks for the tip, those are definately interesting. And the 705e is even cheaper than the X3 720

Probably a bit slower too, but still much more power than my current 4850e... Will be interesting to see reviews when they appear - so far I've only found one on TomsHardware, and that seems promising.

@MikeC: As far as I remember, I saw in a SPCR review or two, something like a AM3-CPU in a AM2+ board, will use more juice, than in a similar AM2(+) CPU in the same board. I havent been able to find it again, so is my memory pleying tricks on me, or is there something about it?

Thanks

Post by **MikeC** » Tue Jun 09, 2009 10:32 am

Thomas wrote:@MikeC: As far as I remember, I saw in a SPCR review or two, something like a AM3-CPU in a AM2+ board, will use more juice, than in a similar AM2(+) CPU in the same board. I havent been able to find it again, so is my memory pleying tricks on me, or is there something about it?

Yes there is. It happens for us consistently. Check the latest AMD CPUs review - and discussion.

Thomas · Post by **Thomas** » Tue Jun 09, 2009 11:46 pm

MikeC wrote:
Thomas wrote:@MikeC: As far as I remember, I saw in a SPCR review or two, something like a AM3-CPU in a AM2+ board, will use more juice, than in a similar AM2(+) CPU in the same board. I havent been able to find it again, so is my memory pleying tricks on me, or is there something about it?
Yes there is. It happens for us consistently. Check the latest AMD CPUs review - and discussion.

Thanks, it's right here: http://www.silentpcreview.com/article949-page5.html - great SPCR expertise !

Dont know how I've overlooked that