When it comes to testing performance RAM, overclocking is very important.
As standard, these modules are programmed to a JEDEC standard of DDR3-1333MHz with timings of 9-9-9 at 1.5V. Without any overclocking, the modules will run as standard at these speeds and settings. What is nice about this memory is that it comes with Intel XMP (Extreme Memory Profiles) support, as many do these days, and that makes overclocking quite simple for the average - advanced user.
This particular HyperX RAM comes with two XMP profiles. The first profile adjusts the system BIOS to run the memory at 1866MHz DDR, while the second one sets the system BIOS to run the memory at 2000MHz DDR, or 2002MHz DDR in this case to be exact.
You can see the validation here.
Once you enable XMP and select profile two, it enables bus overclocking itself and adjusts the bus speed to 143MHz and the CPU clock multiplier stays the same, depending on what CPU you are using. With our Core i7 975 CPU and GIGABYTE X58A-UD7 motherboard, this rendered us a CPU clock speed of 3.432GHz (143 x 24). You will also need to adjust the memory voltage from 1.5 volts to 1.65 volts - in the latest GIGABYTE boards the option to select is 1.66 volts, as there is no exact 1.65 volt option. We also had to adjust the CPU voltage up to 1.4 volts and a range of others to their maximum safe level. You will likely have to do the same as well.
So, the HyperX memory that we were sent works at the rated speed claimed by Kingston and flawlessly once you set the right voltages. We spent a short amount of time trying to hit high memory speeds (2133 and 2100), but didn't have any luck. While extreme overclockers probably won't select this memory as they'll be aiming for DDR3-2500 and well above, for even an enthusiast high-end consumer, this memory should satisfy rather well running at a speedy DDR3-2002 with pretty good timings of 8-8-8-24 (1T).
Important Editor Note: Our maximum overclocking result is the best result we managed in our limited time of testing the memory. Due to time constraints we weren't able to tweak the motherboard to the absolute maximum and find the highest possible FSB, as this could take days to find properly. We do however spend at least a few hours overclocking every motherboard to try and find the highest possible overclock in that time frame. You may or may not be able to overclock higher if you spend more time tweaking, or as new BIOS updates are released. "Burn-in" time might also come into play if you believe in that.