The final phase of the build process is setup and overclocking. When it comes to overclocking I am always interested in finding the best 24x7 settings that balance performance, temperature and sound. It's always great fun trying to find the maximum achievable performance for each component, but if the system is only stable for a few minutes, or sounds like a hair dryer, then in my opinion it's already a failure.
I don't intend for this article to be an overclocking guide, but I will share any rules that I follow, including any tips and tricks that I have picked up along the way. A great starting point is research, specifically to understand the limits of each of your components. For example, what is the maximum recommended power and heat specification for each component you intend to overclock? The best way to find this information is to head over to the manufacturers website or community forums. You can see the details for my new system below:
This information is critical when overcloking as it sets your limits to ensure you don't damage any of your components. It should be noted that the information above is for air cooling, therefore if you have high end water cooling or are using liquid nitrogen (some people do), then you will likely have a different set of limits (due to the lower temperatures).
The next step is to start the testing process. For this I make sure I test each component individually (with all other components at default) to find the maximum value for each. I normally start with the processor, moving to the memory and finally the graphics card, however this is personal preference.
To guarantee a component is stable I normally run a batch of tests that aim to push the system to 100% utilisation (essentially a stress test). Throughout the entire testing process I carefully monitor the voltage and temperature using CPUID HWMonitor and GPU-Z, as well as look for any unusual behavior (display artifacts, software errors, etc). In my opinion, if a component can pass each test without breaching any of the previously mentioned limits (for example temperature) then it can be considered stable. The batch of tests I complete are:
The entire test process takes approximately 2 hours, which can be a pain but is a necessary evil to ensure the system is stable. Once I have found the maximum stable performance / voltage / temperature ratio I normally scale back a touch for my 24x7 settings. At this point I reset to default and move on to the next component. Only once I have data for all the components do I combine the configuration.
Now you know my process, let's dive into the overclocking results. Firstly the max stable overclock results, which can be seen in the table below:
One issue with using cutting edge components is that the software is not mature, which unfortunately resulted in an issue with memory compatibility, meaning the system refused to POST at anything above 1600MHz (11-11-11-28 2N). This is disappointing and will probably result in a 5-10% performance impact (when compared to the sweet spot - 2133MHz). I have spoken with MSI regarding the challenge and they expect to have a BIOS update available soon to resolve the issue.
With that said, the processor and graphics card both achieved very good results. With a 32% increase for the processor and a 33% increase for the graphics card. It should also be noted that the Sapphire HD 7950 OC comes pre-overclocked by 100MHz and therefore this new overclock value can actually be considered a 50% increase over a stock 7950! The load temperatures (Prime95) are a little high for my liking, but the system remained stable and within specification.
The next set of results show my 24x7 settings. Again the memory remains stock, but the processor and graphics cards see a decent increase, with acceptable temperatures.
Overall this is a 26% increase for the processor and a 22% increase for the graphics card (or 37% increase over a stock 7950). This puts the graphics card above AMD's current flagship (Radeon HD 7970), which has a default clock speed of 1050MHz and would cost an additional £100.
For those who are interested I have included screenshots of the BIOS setup and graphics card overclock settings below. It's key to remember that every component is different and therefore simply copying my configuration may not achieve the same results.
The first screenshot shows the "Overclocking Setting" page of MSI's UEFI BIOS. Personally I disable the majority of Intel's power saving features such as EIST, however you should be able to keep these enabled without impacting your overclock.
The second half of the "Overclocking Setting" shows the voltages, that are all set to "Auto" except the VCore which is manually set to 1.250v.
Finally the "CPU Features" page, which are primarily set to "Disabled". Again this is personal preference, as I am happy to run my system at 100% 24x7, without Intel's C-State power saving features kicking in.
Moving on to the graphics card. Although it's possible to overclock using the AMD Catalyst Control Center, you don't get access to the voltages, which is critical if you want to hit the high numbers! This is where the Sapphire proprietary software "TRIXX" comes into play. You can also use Afterburner which is popular tool from MSI that can also be used with other manufacturers graphics cards.
MSI also have a piece of software called "ClickBIOS II" that allows you to modify BIOS settings from within Windows. This apparently works very well, however I'm "old school" and prefer to make my changes directly from the BIOS.
Benchmark Results
There is a good chance you skipped straight to this section. The benchmark results below show my 24x7 settings (outlined above) compared against my old system.
As you can see from the results, the performance increase across the board are quite dramatic. With SuperPi coming in under 8 minutes and a 3DMARK 11 score of 8769! Even the solid sate drives running in RAID0 have shown an impressive increase over the single drive, however without TRIM support it will be interesting to see if this level of performance lasts. For a full breakdown of the results head over to the image gallery.
That's it! Overall my new Ivy Bridge PC has been a pleasure to build and I will continue to tweak the setup over the next few months. My hope is that once the platform matures (new BIOS updates and drivers) I will be able to push it a little harder and get even better results, but even now it's a monster!
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