AMD Phenom II X4 955 Black Edition CPU

Smart Profiles

The other new area is AMD Smart Profiles. Whereas profile saving has already become a standard feature for OverDrive - that's a global setting. Smart Profiles act on a per-application basis, where it can detect specific application .exes running so the CPU can be tailored to overclock or underclock as necessary.

For example, if you're encoding a movie you need more grunt from all your cores - so overclock them all, but if you're playing a lightly threaded game then only overclock a couple of the cores, but underclock the other two to save heat, affording a more stable environment and less wasted energy. What about watching a movie? Turn all those cores way down, undervolt the CPU and the whole PC should quieten down accordingly.

It's a nice idea in practice but we feel the first implementation of this software lacks a particular overclocking finesse, where currently only the main CPU core voltage and some rather obscure multiplier settings are offered. In addition, AMD only has a few gaming profiles available, although it says this will naturally increase over time. However, the company has not stated where these profiles are available from other than "online".

Sothbridge Versus SuperIO?

Another new setting we noticed was the selectable "Environmental Control Source" under the Preference-Setting tab. Asking AMD's performance Guru, Sami Makinen, he explained,

On the SB7xx based motherboards the board vendor can use the SuperIO chip hardware monitoring, or, the SB7xx built-in hardware monitoring instead. Some boards use both too, for example, the Asus M4A79T uses SB7xx voltage input for measuring CPU Vcore and SuperIO for the rest of the voltage readings, temp readings and fan control.

So, if you wish to see CPU Vcore reading on M4A79T you would need to set the source to Southbrige, click apply and then browse back to "board status" tab to read the Vcore value.

Overclocking the Phenom II X4 955

We continued using the Gigabyte MA790FXT-UD5P with the F3l BIOS and Corsair memory, and strapped in the CoolIT Domino ALC cooler to keep things cool.

Cranking up the CPU clocks first we hit a solid 3.8GHz without issue, just as long as we were overclocking from the BIOS because we found it was more reliable to set the main overclock and voltages here first, rather than OverDrive 3.0. 3.9GHz would cause either a hard lock or bluescreen, so we resorted back to OverDrive 3.0 to individually test the cores at 3.9GHz to find which one was flagging. Unfortunately, all of them proved to be unstable. A bit more voltage provide no help so we restarted and added +2 percent on the ACC, hoping to tip them over the edge.

Checking the voltages we could see that even the ALC couldn't withstand the heat output as the cores were slowly climbing above 60 degrees C within a few minutes of Prime95 running - in a hot case this would inevitably be even worse. This was at stock voltage too. Out of interest we pushed the voltage to see if a bit more would help, and we were curious to see how much the Phenom II would be affected by the increase, but we found the temperature leaps quite suddenly as soon as voltage is applied and 1.425V to 1.5V had a detrimental effect far sooner than any benefit.

We can see why the extreme coolers do so well - with no thermal overhead and the freedom to clock to the heavens is why I'm sure these CPUs will keep going beyond 6GHz. However, for us mere mortals, anything less than very high end and potentially noisy cooling, limits the overclocking headroom somewhat more considerably.


Having recently spent quite a bit of time overclocking the Phenom II X3 720 Black Edition as well, we've hit much of the same barriers at 3.8GHz. The choice of motherboard does make some difference, so does the luck of the draw on CPU, but if you're seriously thinking about overclocking a Phenom II, we'd recommend watercooling at minimum.

On the integrated memory clock side of the die, overclocking this proved far more fruitful, landing a stable 2.6 GHz with the memory at 1,600MHz, even though we were again battling with the heat at nearly 65 degrees C.