With any system you will want to see a combination of synthetic testing and real-world. Synthetics give you a static, easily repeatable testing method that can be compared across multiple platforms. For our synthetic tests we use Sisoft Sandra, Futuremark's 3D Mark Vantage and PCMark Vantage, CINEBENCH as well as HyperPi. Each of these covers a different aspect of performance or a different angle of a certain type of performance.
Memory is a big part of current system performance. In most systems slow or flaky memory performance will impact almost every type of application you run.
To test memory we use a combination of Sisoft Sandra and HyperPi 0.99.
The synthetic memory performance of the DFI GF9400 T2RS is pretty good. At stock we see it is right below the reference for Sandra, but when overclocked we see a nice jump to first place.
HyperPi is a front end for SuperPi that allows for multiple concurrent instances of SuperPi to be run on each core recognized by the system. It is very dependent on CPU to memory to HDD speed. The faster these components, the faster it is able to figure out the number Pi to the selected length.
For our testing we use the 32M run. This means that each of the cores on the Core 2 Duo is trying to calculate the number Pi out to 32 million decimal places. Each "run" is a comparative to ensure accuracy and any stability or performance issues in the loop mentioned above will cause errors in calculation.