Test System Setup
Processor(s): Intel Core i7 920 @ 3.8GHz (190MHz x 20)
Cooling: Noctua NH-U12P (Supplied by Noctua)
Motherboard(s): ASROCK P55 Deluxe (Supplied by ASROCK)
Video Card: Gigabyte GTX 285 896MB (Supplied by GIGABYTE)
Hard Disk(s): Western Digital 300GB Velicorapter (Supplied by Western Digital)
Operating System: Windows 7
Drivers: ForceWare 191.07
Today we're all over the place when it comes to CPU speed. We've got everything from 3855MHz to over 4400MHz. We've got the G.Skill modules in three different forms which can all be seen on the previous page.
We've also included the G.Skill Ripjaws at 2000MHz which we recently looked at. The other kit we've included is the A-DATA Xtreme Series, one which offers the same speeds as the Ripjaws, but with slightly more aggressive timings.
We've added so many versions of the PI series because the results were a bit all over the place. While it's a bit hard to explain here, once you have a look at our benchmarks and we start breaking them down, you'll have a better idea.
Let's get started!
Important Note: When modules are overclocked we adjust the BCLK which not only lets us fine tune the MHz out of a module, but in turn increases the overall CPU clock speed. While we always make the effort to include the BCLK and CPU Speed in our graphs, please just make sure that you make note of these when looking at the results. In some tests that don't purely test the memory speed, the extra MHz on offer from the CPU can increase the result. Of course, it's worth noting that having faster memory gives you the ability to run your CPU at a higher speed.
wPrime uses a recursive call of Newton's method for estimating functions, with f(x)=x2-k, where k is the number we're sqrting, until Sgn(f(x)/f'(x)) does not equal that of the previous iteration, starting with an estimation of k/2. It then uses an iterative calling of the estimation method a set amount of times to increase the accuracy of the results. It then confirms that n(k)2=k to ensure the calculation was correct. It repeats this for all numbers from 1 to the requested maximum.
When we clocked our CPU right up, the wPrime numbers just went crazy. For some reason the 1024M and 32M tests took significantly longer than the other kits which actually come in slower. As for the kit at 2200MHz DDR and 2242MHz DDR, due to the lower CPU speed we can see that the performance isn't as attractive.