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 Everest Ultimate, Sisoft Sandra, Futuremark's 3DMark 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 flakey 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.
I was surprised to see that the ASUS P55 board with the core i5 750 did not do as well as the ASRock. I was so surprised that I ran the test multiple times to make sure it was accurate. However, even after several runs I will still getting the same results.
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 four physical and four logical cores for the i7 and the four physical cores of the i5 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.
Despite the showing in memory bandwidth, the P7P55D-E Pro shows that it can handle heavy computational loads by giving a great HyperPi showing. Here it out does the ASRock P55 Deluxe fairly easily.