Section 1 Subsystems -
Memory -
Memory performance is very important on a motherboard, especially when you have a CPU with multiple cores and threads. If you have slow memory your cores and threads can become starved for data to execute. To test memory performance we run both Sisoft’s SANDRA and AIDA64. These two combine to not only give us accurate numbers but to validate each other. For testing at stock speeds the memory is hard set to 1333MHz while overclocking testing is done at the highest stable speed for the voltage of 1.65v this is due to the different memory dividers for each CPU. As such, the memory speeds will vary greatly. This means that the overclocked numbers are a little misleading and while they can show a trend are really only included to show if a board has a problem with memory performance at high clockspeeds.
Wow, now this is some impressive memory performance. However, this is mostly due to the CPU and not the motherboard. It is true that with proper tuning in the BIOS and the right trace tuning you can improve on this but typically the improvement is not much more than 5 or 10%. We do wonder what the memory performance will look like once Intel releases the final BIOS for this board though.
We should also mention that for our testing we were not using a true Quad Channel Kit, but two dual channel kits.
Drive performance -
Drive performance is also one of the major subsystems that goes to make up the performance of a motherboard. For our testing we use Sandra and AIDA64 again. We only test with single drives for each type of controller present on the motherboard (unless it is a professional product where we will use RIAD 5 and/or 10). We have also begun using a Seagate PS-110 USB 3 external HDD for our USB 3.0 performance. As a side note, we include the overclocked numbers here to make sure (again) that you are not going to see a major drop in performance due to minor instabilities at high clock speeds.
Drive performance on the X79SI was about where it should be and very comparable to the X58 and other Intel Chipsets. As we mentioned before we were unable to test the USB 3.0 controller once we hit our top “stable” clock of 4.5GHz. This was disappointing, but in the end we feel this is a BIOS or driver issue and one that can probably be fixed in a relatively short time frame.
Power -
Power efficiency is another of those misnomers that we get caught up in. We hear about idle states and power gates. But what does that mean to you and I? On the surface having power management that reduces idle power sounds great and can be a benefit to someone that leaves their system on for long periods of time (and inactive) but how a system handles power under load and the delta between the two states is often more important than the idle power usage numbers. We use only P3 Kill A Watt instruments for measuring power. 
The power draw from the X79SI with a single CPU (an AMD 5870) was not that bad considering the size of the CPU and the fact that you are powering an additional RAM slot by default. We found that at idle the X79 did very well with an average power draw of only 104 Watts from the wall socket. Under the typical load of playing a game the X79Si was topped only by the Asus Rampage III Black
Cooling (Board Level) -
Board level cooling is an important factor in product performance and longevity. Components like the chipset, VRM modules and even capacitors need to be kept relatively cool to prevent failure. As these parts are made of silicon, they have a thermal breakdown threshold; or melting point. At that temperature the actual transistors built into chip will begin to deform and break down. Granted, the threshold is often very high, but you still need to make sure that components stay away from this level of heat for longer product life. 
The board level cooling was not too bad on the Intel X79SI. We honestly expected it to be less than stellar but in the end it out did the other guys boards that we tested. We would highly recommend that you have good air flow though as with everything going on you could easily create a pocket of hot air that would hinder your performance and component life. 
Audio -
Audio is highly subjective. What we find pleasing may sound “off” to you. That is always going to the problem with testing audio; results will vary too widely depending on the tastes of the listener. However, there are ways of measuring the audio output with an objective ear. There is also the issue of audio causing performance issues in gaming and video playback. The reason this is a potential source of concern is that all onboard audio CODECs (Compression/Decompression) are CPU controlled. This means that while the audio chip controls the audio levels and effects of the audio the actual work is done on the CPU. Usually this will not be a problem with today’s powerful CPUs. Even the lower and consumer level products can handle high-end audio these days. But again there is the chance that a bad design or software will hinder your system and performance. On the other side the limits of board space, cost, etc will also prevent the level of audio quality you can get from an add-in board. We test all audio parts with three media types, Movie (DVD), MP3 Music, and Gaming. These are pushed to our Tec On model 55 Tube Amp to see if we can detect any signal issues in the reproduction. The audio on the Intel X79SI is ok. It is not going to impress any audiophile out there, but it is good enough to make most users happy and while it is not going to add anything to your gaming experience, it will not take anything away from it either.
Networking -
This one is something that is a requirement anymore. If you have a computer, the chances are good (like 99%) that you are also connected to high-speed internet. With this you need a good and solid LAN chip to make sure that your data flows properly out and back. As this is an Intel motherboard, it of course comes with Intel Network Controllers. These are arguably the best and most compatible LAN controllers you can get out there. We had absolutely no issues with the network performance including pulling our full testing package over from the storage server (a full 23.9 GB of data). The network felt quick and responsive.
