In this blog post, I tell the story of how we achieved the first ever 9 GHz and 9.1 GHz CPU Frequency overclock by using liquid helium cooling.
What is (Extreme) Overclocking?
Overclocking is the art of increasing a processor’s operating clock frequency beyond the warranted manufacturer specification. The practice has been around for as long as processors had a clock frequency. Consumers do it to achieve extra (free) computing performance and companies do it to showcase the reliability of their products.
Extreme overclocking involves the same process of increasing the operating clock frequency beyond the warranted specification but with the use of exotic cooling techniques such as dry ice, liquid nitrogen, and liquid helium. The primary impact of such exotic cooling is that the significantly reduced operating temperatures substantially improve the overclocking headroom. That allows the user to achieve operating clock frequencies that yield record-breaking performance.
I have been deeply involved in the (extreme) overclocking community for over two decades as a reviewer at Madshrimps, an administrator and later owner of HWBOT, and currently as a content creator at SkatterBencher. I’ve participated in several overclocking regional and world championships and achieved several hardware class and overall benchmark overclocking records.
One of the first times I ever tried extreme overclocking was to push the Athlon 64 3000+ to 3.6 GHz back in 2006, nearly 18 years ago when I was 17 years old. That result still stands as the 4th highest overclock for that particular processor. I actually published a report about that session on Madshrimps!
However, few, if any, of those achievements match the grandeur of being the first to achieve a 9 GHz CPU frequency.
CPU Frequency Overclocking World Record
I track the history of the CPU frequency overclocking world record on the SkatterBencher website. The record has a long history which was in part fueled by the frequency race among semiconductor manufacturers and in part by human’s desire to compete.
The pace of achieving frequency milestones was excruciating in the first decade of the millennium:
- First 1 GHz on October 7, 1999, with an AMD Athlon 650 MHz
- First 2 GHz on December 3, 2000, with an Intel Pentium 4 1.4 GHz
- First 3 GHz on September 5, 2001, with an Intel Pentium 4 2.0 GHz
- First 4 GHz on March 27, 2002, with an Intel Pentium 4 2.4 GHz
- First 5 GHz on July 3, 2003, with an Intel Pentium 4 3.2 GHz
- First 6 GHz on May 25, 2004, with an Intel Pentium 4 560
- First 7 GHz on August 9, 2005, with an Intel Pentium 4 670
- First 8 GHz on January 22, 2007, with an Intel Pentium 4 631
Intel famously predicted in 2000 that it would achieve a 10 GHz operating clock frequency at an operating voltage of 0.85V by 2005.
However, around 2005 semiconductor vendors realized that increasing the clock frequency as a means to increase compute performance also meant prohibitively increasing the power consumption. As the frequency race ended, the multi-core race began. Semiconductor companies focused on using the ever-smaller transistors to add more cores to improve compute throughput rather than increasing the operating frequency.
Perhaps as a consequence of the reduced focus on achieving ever-higher operating clock frequencies, the CPU frequency overclocking world record stalled for many years. Since 2007, only two CPU micro-architectures have been able to break the world record: AMD Bulldozer and its direct successor Piledriver. Ultimately, AndreYang achieved nearly 8.8 GHz on November 19, 2012, well over a decade ago.
For a variety of reasons, the AMD and Intel micro-architectures released in the years following Piledriver never came close to achieving frequencies surpassing 8 GHz.
| Year | Company | Architecture | Processor | Fmax | Link |
|---|---|---|---|---|---|
| 2011 | Intel | Sandy Bridge | Core i5-2500K | 6382 | http://valid.x86.fr/pnum14 |
| 2012 | AMD | Piledriver | FX-8350 | 8794 | http://valid.x86.fr/lpza4n |
| 2012 | Intel | Ivy Bridge | Core i7-3770K | 7247 | http://valid.x86.fr/559ntl |
| 2013 | Intel | Haswell | Core i7-4770K | 7181 | http://valid.x86.fr/240rw0 |
| 2014 | AMD | Steamroller | Athlon X4 870K | 6260 | https://valid.x86.fr/g5btin |
| 2014 | Intel | Broadwell | Core i7-6950X | 5805 | http://valid.x86.fr/1zcvfi |
| 2015 | AMD | Excavator | Athlon X4 845 | 4903 | http://valid.x86.fr/0kl2u6 |
| 2015 | Intel | Skylake | Core i7-6700K | 7056 | http://valid.x86.fr/8v1dq5 |
| 2016 | Intel | Kaby Lake | Core i7-7740K | 7562 | http://valid.x86.fr/gh9ifj |
| 2017 | AMD | Zen | Ryzen 5 1600X | 5905 | http://valid.x86.fr/8gvc4s |
| 2017 | Intel | Coffee Lake | Core i9-9900K | 7613 | http://valid.x86.fr/zmnzmz |
| 2018 | AMD | Zen+ | Ryzen 7 2700X | 6000 | https://valid.x86.fr/qytcc1 |
| 2019 | AMD | Zen 2 | Ryzen 5 3600XT | 6155 | https://valid.x86.fr/8ki3vn |
| 2020 | AMD | Zen 3 | Ryzen 5 5600X | 6175 | http://valid.x86.fr/yrp0cu |
| 2020 | Intel | Comet Lake | Core i9-10900K | 7707 | http://valid.x86.fr/cr6b2e |
| 2021 | Intel | Rocket Lake | Core i9-11900K | 7337 | http://valid.x86.fr/sqt4ap |
| 2021 | Intel | Alder Lake | Core i9-12900KS | 7800 | http://valid.x86.fr/nheapx |
| 2022 | AMD | Zen 4 | Ryzen 9 7950X | 7471 | http://valid.x86.fr/mlcmxz |
Intel Raptor Lake Architecture
During the Intel Innovation 2022 event in September 2022, Intel announced the Raptor Lake processor architecture as the successor of Alder Lake. Two slides stood out at that event.
First, Intel claimed the upgraded Intel 7 process, featuring the 3rd generation SuperFin transistors, would bring peak frequency improvements of +600 MHz. Second, Intel teased the very first processor clocked at 6.0 GHz out of the box. This processor would later become known as the Core i9-13900KS.
The highest frequency achieved on Alder Lake is 7800 MHz. So even with the improved Intel 7 process, no one expected Raptor Lake to touch AMD’s 8.8 GHz frequency record.
But that all changed one month later when the ASUS ROG overclocking team achieved 8812.85 MHz, breaking the decade-old world record. The most remarkable part about that overclocking result is that it was done with liquid nitrogen, not liquid helium.
Liquid Helium for Overclocking
The obvious reason why liquid helium is used by overclockers is that it can cool the processor down to near absolute zero temperature. In theory, liquid helium (4.2K) provides a 73 kelvin advantage over liquid nitrogen (77.36K). Lower temperatures usually increase the overclocking headroom.
Modern Intel processors are surprisingly good at handling extreme temperatures. With a combination of the right motherboard and voltages, a lot of processors will operate without problems at minus 196 degrees Celsius.
Helium is indeed a rare element on earth and, thus, there’s a finite amount available. It’s a non-renewable resource too, so some claim using helium for overclocking records is an unacceptable waste of scarce resources. However, keep in mind that during an overclocking world record attempt, usually only 100 to 250 liters of Helium is consumed. That’s a blip of the estimated 160 billion liters produced annually.
Furthermore, in the words of Max Planck, the 1918 Nobel Laureate in Physics, “Scientific discovery and scientific knowledge have been achieved only by those who have gone in pursuit of it without any practical purpose whatsoever in view.”
First 9.0 and 9.1 GHz Clock Frequency
Following the exciting record-breaking achievement of Raptor Lake in October 2022, the ASUS ROG overclocking team strongly considered using liquid helium to improve the CPU frequency overclocking world record. This is where my story begins as I was invited to join the overclocking team for the attempt.
We achieved the first 9 GHz on December 9, 2012, in preparation for the Intel Core i9-13900KS product launch. We initially aimed to set the record with the KS, but turned out that the 13900K was a one-of-a-kind chip. It could run colder and faster and was the only processor capable of breaking the 9 GHz barrier. For the occasion, Intel had also sent out a video crew.
We achieved 9.1 GHz for the first time on March 7, 2024, while preparing for the Intel Core i9-14900KS product launch. The Core i9-14900KS is the final evolution of the Raptor Lake processor architecture. It represents the best of the Raptor Lake silicon, symbolized by its out-of-the-box frequency of 6.2 GHz.
Unfortunately, this time around there was no professional film crew present to capture the moment. However, I did put together a video detailing the event.
Conclusion
I’ve been around the (extreme) overclocking scene for a very long time and in very different capacities. While I’ve been deeply involved since I was a teenager, never could my younger self have imagined I’d be part of this little aspect of computer history.
Being a part of the team that achieved the first 9 GHz CPU clock frequency will be something I’ll treasure for the rest of my life!
