By Jake Crimmins posted Dec 19th 2011
Overclocking the new AMD Bulldozer CPUs on liquid nitrogen is easy, fun and affordable even for a beginner. The new generation of Bulldozer CPUs are reaching speeds near or over 8GHz on liquid nitrogen. Along with high CPU frequencies the processors are able to run memory at high frequencies as well. In this blog I am going to show you the basic template of the settings I use to reach high core and memory frequencies on liquid nitrogen. Be careful though because overclocking on liquid nitrogen voids most warranties and can kill your hardware!
If you haven't already, you may want to watch this Corsair video on how to prep your motherboard to run on liquid nitrogen. Since most AMD Bulldozer CPUs don't have cold bug issues you can normally run them with a full liquid nitrogen pot. This means your CPU would be running near -192° C. Once you have your CPU cooled down you can start overclocking it.
This ASUS Crosshair V Formula motherboard has a nice Extreme OC profile built in. You can load the profile which automatically disables some extra features. These features are not needed for extreme overclocking. It also changes a few other settings in the bios to allow you to run higher voltages as well. After loading the profile, I started off by setting my multiplier to 30x and raising the FSB frequency to 240MHz. This would mean the CPU clock would be 7.2GHz. Next the memory frequency and CPU/NB frequency are set to run right around 2000MHz. The HT Link Speed is set to the lowest setting available. I will then adjust the FSB frequency in windows to achieve my final overclock.
Now it is time to start raising voltages in the bios. I start out by giving the CPU 1.95v, this is very high and can damage your processor so you need to make sure it is properly cooled. Next the CPU/NB voltage is set to 1.6v, you may need to experiment with this voltage depending on your CPU and what FSB you want to run. The last voltage to be set is the memory voltage at 1.7v.
Finally if you are going after the maximum frequency your processor can run disabling some of the cores can help dramatically.
Now comes the fun part! You can save you changes and boot into Windows. You can now use ROG Connect to raise the FSB frequency. With this and some minor voltage adjustments you should be able to reach frequencies in the high 7GHz range or even 8GHz if your CPU is good. My CPU was able to reach just shy of the 8GHz mark!
Overclocking memory for the maximum frequency uses almost the same configuration as above. The first thing you will notice is the CPU multiplier has been dropped to 14x. This will let us run memory at high frequencies without worrying about the CPU frequency going to high. It also relieves some stress on the CPUs memory controller. I set the FSB setting to 280MHz because I know the Dominator® GT CMGTX6 DDR3 memory module I'm using can boot that high. Depending on what memory you are using you may need to lower the FSB or memory divider to ensure the machine will boot. Since I am going for overall speed I am using a single 1GB CMGTX6 DDR3 memory module that I've pre tested to do frequencies over 3.4GHz. In order to set and boot into Windows at 280MHz on the FSB — the memory frequency is set to the 2400MHz divider and with the 280MHz base clock it gives a memory frequency of 3360MHz. The CPU/NB frequency is kept to the same frequency as the memory and the HT Link speed is set to the lowest setting.
The CPU voltage is set to 1.7125v which was required to boot in at this higher FSB and memory speed. The CPU/NB voltage was set to 1.68125v which again was required to boot into Windows. Finally the memory voltage was set to 1.75v.
The memory timings were set to 11-13-13-31-2T which was the loosest they could be set to on this motherboard.
Once in Windows I used ROG connect to raise the FSB and memory voltage. I set the memory voltage to 1.8375v and then I was able to walk the FSB up to 290MHz. This is just slightly better than my previous results I was able to reach in one of my earlier blog posts. This meant my memory was running at almost 3500MHz!
Even if you are just getting into extreme overclocking you should be able to get some great results. Overclocking Bulldozer was very easy and it was a lot of fun to reach frequencies that just weren't possible with previous generation AMD and Intel CPUs.