The Generation Gap
The Generation Gap
Intel tells us that the architectural changes going from Nehalem to Sandy Bridge have resulted in a significant increase in performance across the board. Besides those marketing numbers, we have seen for ourselves the difference between our Sandy Bridge samples and the older processors. But to really narrow down the impact of this shift in architecture, we had to compare apples to apples, or as close to that as possible.
For this scenario, we took a Core i7-875K processor and downclocked it to 2.8GHz. We did the same for the Core i7-2600K and then we disabled Turbo Boost on both. The reason for choosing 2.8GHz is that both processors have different bus speeds (133MHz and 100MHz respectively) so we had to choose a clock speed which could be replicated on either side by changing the multipliers.
HyperThreading remained on both, so technically there are up to eight threads active. Hence we now have two processors of each generation at 2.8GHz, with an identical amount of L3 cache (8MB). Of course, the rest of the test system is similar, down to the drivers. The only difference is in the chipset.
Here then are selected results between the two Core processors at 2.8GHz.
From these three benchmarks, we found that the Sandy Bridge Core i7 was at least 20% faster than its predecessor in SYSmark 2007 and PCMark Vantage, system suites which measure the overall performance of your PC. In the more specialized Cinebench, the performance gain using the Sandy Bridge CPU was only about 14%.
So if you're one of those mulling over the idea of upgrading from an existing Nehalem Core processor, this performance gap between the old and new is something to consider. Those with a higher-end Core i7 may choose to wait for a more compelling difference before upgrading.