phenom II AM2+ vs AM3?
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phenom II AM2+ vs AM3?
which would you get for a quiet pc?
thanks!
thanks!
Last edited by intx on Sun Feb 08, 2009 5:13 pm, edited 2 times in total.
Do you mean that the Phenom II 940 system uses only four more Watts than the Phenom II 810 system at load? That is rather strange. I wonder if Anandtech did not load the CPU enough; here is a different review where the difference is 23 Watts under load:
http://www.hexus.net/content/item.php?i ... 13&page=11
http://www.hexus.net/content/item.php?i ... 13&page=11
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Re: phenom II AM2+ vs AM3?
If it were me I'd go for the cheapest one which makes me look at the X3 710 and 720.intx wrote:which would you get for a quiet pc?
thanks!
* AMD Phenom II X3 720 - 2.8GHz, 7.5MB Cache - Black Edition in PIB at qty price of $145
* AMD Phenom II X3 710 - 2.6GHz, 7.5MB Cache - Available in PIB at qty price of $125
especially considering the X3 720 beats the X4 910 in most tests. (correction, meant to say it beats the X4 940 in some tests).
Use it in AM2+ for the low price now. If you want to upgrade wait for lower TDP parts to make the AM3 transition later when DDR3 is cheaper than DDR2. Until that price inversion occurs I'm not that interested in DDR3.
Last edited by dhanson865 on Wed Feb 18, 2009 9:18 am, edited 1 time in total.
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intx wrote: price difference is like $30.
The only true AM3 boards are $140+, or they are "AM2+/AM3" which means they are really AM2 boards (DDR2 memory, etc.).
REAL AM3 boards
Fakes
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Re: phenom II AM2+ vs AM3?
I noticed this also. This doesn't make sense. It has to be a bad test with s/w that doesn't use all cores.dhanson865 wrote:...
especially considering the X3 720 beats the X4 910 in some tests.
...
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Like others, I would think a 95 tdp would be much better than a 125 tdp. However, the power usage tests I've seen don't bear this out. In fact, under load, they seem to be about the same.
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Re: phenom II AM2+ vs AM3?
No it makes perfect sense. Let me spell it out for you.seemingly.random wrote:I noticed this also. This doesn't make sense. It has to be a bad test with s/w that doesn't use all cores.dhanson865 wrote:...
especially considering the X3 720 beats the X4 910 in some tests.
...
* AMD Phenom II X4 910 - 2.6GHz, 8MB Cache (as in 6MB L3 and 512K per core)
* AMD Phenom II X3 720 - 2.8GHz, 7.5MB Cache (as in 6MB L3 and 512K per core)
A. 2.8 GHz is higher than 2.6 GHz. Some bechmarks favor clock speed over number of cores.
B. Since the X3 has the same size L3 caches and one less core it has more L3 cache per core or in other words 6/4 is less than 6/3. Some benchmarks favor more cache per core.
Pick a reason but there are advantages to the X3 720 over the X4 910.
Further I made a mistake and meant to mention in that quote that it also sometimes beats the X4 940 which is 3.0 GHz. In those cases only B applies but we add C.
as per http://www.anandtech.com/cpuchipsets/sh ... i=3512&p=1 or http://en.wikipedia.org/wiki/List_of_AM ... _X4_series you can see
C. The Phenom II X4 940 is 3.0 GHz on the top end but also has a 1.8GHz clock for the Hypertransport bus. The X3 720 is only 2.8 GHz on the top end but uses a 2.0 GHz clock for the HT bus. This gives benefits on benchmarks that need faster access to memory.
In short there is no single CPU from AMD that is the fastest at all benchmarks. Given that I'm happy to grab the cheaper one that has the same large L3 and the faster clock for the HT.
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FWIW everything I said was from the standpoint of stock speeds. Overclocking is not something that is addressed by any of my posts in this thread.joelmusicman wrote:I believe that the better performance for the x3 has to do with its superior overclockability and more L3 cache per core. Therefore, single-threaded or dual-core only apps would do better on the triple core Phenoms.
Especially when underclocking and undervolting are more in the theme of SPCR than overlclocking is.
If you're interested in ATX format I can recommend first hand Asus M3N-HT/HDMI.
From a week's usage experience i can tell it's good - full SpeedFan control over at least 3 headers and nice passive cooling, loads of expansion slots.
It's also supposed to undervolt/overclock really well, but I haven't yet found time to check it.
From a week's usage experience i can tell it's good - full SpeedFan control over at least 3 headers and nice passive cooling, loads of expansion slots.
It's also supposed to undervolt/overclock really well, but I haven't yet found time to check it.
Who cares about the mobos? The RAM is still way too expensive (presuming we're talking about real DDR3 AM3 mobos)...jeekub wrote:You get more headroom for upgrades later on if you go for Phenom II - such as DDR3's and quicker HT.
What's more, you can stick it in AM2+ socket MoBo and wait for the AM3 ones to drop the novelty price tag.
The reviews for that board are pretty low. Sounds like a number of people have had driver issues. What OS are you using?jeekub wrote:If you're interested in ATX format I can recommend first hand Asus M3N-HT/HDMI.
From a week's usage experience i can tell it's good - full SpeedFan control over at least 3 headers and nice passive cooling, loads of expansion slots.
It's also supposed to undervolt/overclock really well, but I haven't yet found time to check it.
... when it comes to computing performance.Luminair wrote:am3 and ddr3 DONT MATTER ...
There are other issues that would make me, the cheapskate, go for AM3 and DDR3:
- Future upgrades. Prolonging the life of the computer by adding more RAM and perhaps replacing the CPU two or three years from now. At that time it will be difficult and expensive to find an AM2+ CPU, and DDR3 will be cheaper than DDR2.
- Power/noise. DDR3 is more energy efficient than DDR2.
Cheers
Olle
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Re: phenom II AM2+ vs AM3?
That wouldn't be the hypertransport bus but the unicore (intergrated memory controller/L3 Cache.)dhanson865 wrote: C. The Phenom II X4 940 is 3.0 GHz on the top end but also has a 1.8GHz clock for the Hypertransport bus. The X3 720 is only 2.8 GHz on the top end but uses a 2.0 GHz clock for the HT bus. This gives benefits on benchmarks that need faster access to memory.
The only thing I didn't like about the Phenom II X3 720 is not all software uses the third core, and as a result it falls below the Core2 E8400 instead of being ahead when the third core is used.
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Only on an earlier production run though unfortunately.DanceMan wrote:Phenom II X3 720
There are reports of people enabling the fourth core on some of these. Worth checking out.
It was earlier known that only chips belonging to 0904 (fourth week of 2009) batch of the processors would be able to respond to the mod successfully, but now, a fresh finding by German website Hartware.net suggests that even chips made in the 51st week of 2008 batch responded to the mod, and the fourth core could be enabled. Hartware.net used Biostar's TA790GX A2+ motherboard for the feat.