A Little Overclocking: Record Set for Phenom II under Linux
For real overclocking you need liquid nitrogen and helium. All you need to do in winter is open your window.
The Phenom II Z940 processor from AMD provides a maximum clock rate of 3 GHz out of the box. Now news from Slashdot.com reports that a group of overclockers has increased the rate to 6.5 GHz, an apparent new record. The trick was to get temperatures down to minus 232 degrees Celsius, close to absolute zero.
We didn't want to go to such extremes in our own testing, so we simply put the test system on the window sill at 5 degrees Celsius. We then did an overclocking, even though our mainboard was a bit old for the Phenom II.
The Asus M3A78-EM motherboard provides a few tuning possibilities, but the BIOS completely ignored the frequency multiplier setting. Instead we used one of the three available overclocking profiles for five, eight and 10 percent faster rates. We started the first test at 5%, but soon discovered to our surprise that /proc/cpuinfo showed a 3,000 MHz frequency even under load. The benchmark results then improved markedly.
As a control, we raised the Z940 to the maximum 3.3 GHz allowed by the overclocking profile and, alas, the benchmark results were even better. Power consumption was also higher, showing that the CPU was truly running at 3,000 MHz, even though it had little effect on the 64-bit openSUSE 11.1 kernel.
We then wanted to see how far we could go and raised the rate above the reference clock to 3.75 GHz. The result was a panic error from the openSUSE and Ubuntu 8.10 kernels and the CPU could no longer keep up. Running at 3.375 GHz was still OK for the Phenom II, but 3.5 and 3.6 GHz showed sporadic crashes. An even colder environment and better test technology might have pushed the Z940 a bit further.

A glance at the graph might prompt the reaction that the the Phenom II is eight times faster than the Atom. Not quite correct, because the graph shows only a single core. In actuality, the AMD CPU can convert four .wav files with a factor of 38 into Ogg Vorbis format, working at about double clock rate with a resulting factor of 30 faster than the Atom N270.
Naturally we also started a short test on the i7 system. Needless to say the AMD clearly beat the equally clocked quad processor from Intel. The i7 (without overclocking) reached a factor of 33. Our Ffmpeg benchmark, however, proved the Intel ahead by a nose because of its hyperthreading support, and the AMD CPU had to be clocked at about 3.8 GHz to achieve the same results.
Comments
comments powered by DisqusIssue 259/2022
Buy this issue as a PDF
News
-
Titan Linux is a New KDE Linux Based on Debian Stable
Titan Linux is a new Debian-based Linux distribution that features the KDE Plasma desktop with a focus on usability and performance.
-
Danielle Foré Has an Update for elementary OS 7
Now that Ubuntu 22.04 has been released, the team behind elementary OS is preparing for the upcoming 7.0 release.
-
Linux New Media Launches Open Source JobHub
New job website focuses on connecting technical and non-technical professionals with organizations in open source.
-
Ubuntu Cinnamon 22.04 Now Available
Ubuntu Cinnamon 22.04 has been released with all the additions from upstream as well as other features and improvements.
-
Pop!_OS 22.04 Has Officially Been Released
From the makers of some of the finest Linux-powered desktop and laptop computers on the market comes the latest version of their Ubuntu-based distribution, Pop!_OS 22.04.
-
Star Labs Unveils a New Small Format Linux PC
The Byte Mk I is an AMD-powered mini Linux PC with Coreboot support and plenty of power.
-
MX Linux Verison 21.1 “Wildflower” Now Available
The latest release of the systemd-less MX Linux is now ready for public consumption.
-
Microsoft Expands Their Windows Subsystem for Linux Offerings With AlmaLinux
Anyone who works with Windows Subsystem for Linux (WSL) will now find a new addition to the available distributions, one that’s become the front-runner replacement for CentOS.
-
Debian 11.3 Released wIth Numerous Bug and Security Fixes
The latest point release for Debian Bullseye is now available with some very important updates.
-
The First Alpha of Asahi Linux is Available
Asahi Linux is the first distribution to fully support Apple Silicon and is now available for testing.
Re:Voltage
But perhaps you can post your settings, so other readers can test them as well.
Voltage ?
Have you increased the voltage while OC ? I have the same processor and I could bum it to 3.8 with a little bump in voltage.. once can achieve 4ghz + @ increased voltage and with the help of a better cooler and cooling solution.. No Nitrogen and Helium needed
Regards