Starting out our Intel Core i7 3770K benchmarking under Linux are some of the OpenMP-based Fortran-written NPB tests from NASA. In the BT.A test from the NAS Parallel Benchmarks, the Intel Core i7 3960X with its six physical cores plus Hyper Threading reigned supreme in this heavily multi-threaded test. The Intel Core i7 3770K at its stock speeds was 10% faster than the Intel Core i5 2550K and its performance was boosted by another 11% when overclocking the CPU to the modest frequency of 4.30GHz.
With the IS.C test in NPB, which isn't heavily multi-threaded like the rest, the Core i7 3770K comes out well ahead of all other processors -- including the Core i7 3960X. The i7-3960X and i7-3770K both top out at 3.9GHz for their Turbo Boost frequency by default, but even with more physical and logical cores with the Sandy Bridge Extreme, the Ivy Bridge desktop processor was faster. The stock Core i7 3770K was 8.8% faster than the Core i7 3960X and this boost was widened when overclocking. The Core i7 3770K was nearly twice as fast as AMD's current top-end desktop processor, the AMD FX-8150 Bulldozer. For IS.C, the i7-3770K was 14% faster than the popular Sandy Bridge i5-2500K.
With LU.A being able to scale well with multiple cores, the Core i7 3960X obviously comes back out ahead of the quad-core Core i7 3770K plus Hyper Threading. Overclocking the i7-3770K to 4.30GHz yielded a 12% boost in performance for this scientific benchmark.