Alright, it is finally time to have some fun. Before we get to the good stuff of absolute maximum benching, let's see what our AMD Phenom II 940 engineering sample is capable of for 24/7 operation. Naturally we start off with a couple photos so everyone can see exactly how the setup looked during testing.
As we can see, there is one fan pulling on the Ultra-120 and a second fan somewhat pushing, but it is mainly there to get some airflow over the heat pipe setup and the memory. We can also see that we definitely are not using a Thermalright Ultra-120 eXtreme, and just the older Ultra-120. Temperatures may have been a little better with an eXtreme but the Ultra-120 holds its own, even with quad cores. With full disclosure complete, let's see what this setup was capable of for our standard 24/7 stability testing.
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After a bit of fiddling with ratios and voltages, we were able to steady the ship and sail straight ahead right around
3750MHz with a HT bus frequency of 2250MHz and a healthy NB clock of 2500MHz. Overclocking the Phenom II is absolutely no different than the first generation Phenom. With the Phenom II 940, the CPU multiplier is un-locked but clocking the HTT provides the ability to adjust multiplier combinations to provide the best combination for performance. Having the NB frequency at 2500MHz and the memory running at DDR2-1000 4-4-4 provides a very nice memory sub-system while keeping voltages relatively low. A few reports had AMD stating 1.55v on air would be safe with these Phenom II processors so we stuck to that, but don't take our word for gospel, we are just going off of what we "heard".
The Gigabyte GA-MA790GP-DS4H really was a breeze to handle. All voltages aside from vDIMM, vCORE, and vNB were left at default and getting the Phenom II to dance was a painless chore, even for someone like myself who has been out of the AMD clocking scene for a little while. While we are looking at a stable air overclock, we might as well take a quick peek at the temperatures this processor is achieving at an overclock of this magnitude. Below is a chart from SpeedFan depicting the average temperatures of the four core readings in red, and the "CPU" temperature in green from a loaded state to idle using Prime95 Blend with the above overclock.
Ambient temperature was between 21C~23C as measured from directly above the open air setup. As we can see, if these readings are accurate, that temperatures are quite low. The problem is that with stock voltages and frequencies, we see idle temperatures up to 10C below ambient temperature. Notice that at 1.55v we see idle temperatures of 21C in the graph above when we know that ambient is above even that. This means temperature sensors are way off or there are really poorly calibrated idle temperatures at the very least. Based on what we have seen with this processor over the last few weeks. We would venture a guess that the current temperature readings are 10C~15C lower than they should be. Keep this in mind when getting all excited about the temperatures of these new Phenom II processors, for now. With nothing much else to discuss, let's see what we could push this processor to with air cooling. For these benchmarks, we decided that upping the voltage to 1.65v in the BIOS would be acceptable for short runs, so these results are with the slightly elevated voltage from our 24/7 testing as the maximum.
CPU-Z Validation
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CPU-Z Validation | Hexus PiFast
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Super Pi 1M
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 | Super Pi 32M
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WPrime - 32M
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 | WPrime - 1024M
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Aquamark 3
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 | 3DMark 01
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3DMark 03
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 | 3DMark 05
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3DMark 06
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 | 3DMark Vantage - Performance w/o PhysX
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The party started relatively high and slowly worked its way down as more cores got involved. Overall the results are pretty shocking for an AMD processor, but at the same time by no means the highest we have seen up to this point for these new Phenom II's. Other users have been posting results that far surpass these, but there are just as many results in about the same range as us. This leads us to believe that without significant changes to the Phenom II process, our results found here today will be about the average that we should expect from retail samples out today. Here is a quick chart to show the scaling of the clocks with the benchmarks ran.
The air cooling overclocking is a pretty flat chart. At this point in the game, temperatures aren't playing a huge role and CPU voltage is likely the limiting factor. The multi-core benchmarks really hold their own against the single core results. This trend is about to change when we move on to the sub-zero cooling setups.
