Let's start with gaming... 'cause that's what I assume is what you will primarily be doing. Note that 1680 x 1050 resolution is used because at higher resolutions games tend to be bound more by the performance of the video card. What this means is that at higher resolution, the difference in performance should be less. However, this is a CPU comparison, not a video card comparison. The Core i5-2500k will be the baseline. Also, this benchmarks excludes overclocking. Lastly, I will exclude synthetic benchmarks (SysMark & 3DMark11) to shorten my post and these type of benchmarks do not generally translate to real life benchmarks.
Rule of thumb: If all you have are synthetic benchmarks, then okay use them if necessary. Otherwise, toss them out with the rest of the trash.
The Core i5-2500k was able to pump out 155.29 frames compared to 86.25 frames for the FX-6100.... Result FX-6100's performance is 55.54% of the i5-2500k. Based on the video card used in this test, if the resolution was bumped up to 1920 x 1080 or higher, the Core i5-2500k would still outperform the FX-6100.
This indicates that as long as the CPU is fast enough, there will not be much impact on performance in Crysis 2. This benchmark is more evenly matched since the FX-6100 has 94.17% of the i5-2500k's performance.
Similar to Far Cry 2, Metro 2033 benefits from a faster CPU. At 19.4 FPS, the FX-6100 only has 37.74% of an i5-2500k.
139.16 FPS for the i5, 102.56 FPS for the FX-6100. The FX has 70.5% performance of an i5-2500k
Like nearly all strategy games, StarCraft 2 puts a lot more emphasis on the CPU, than the video card. Core i5-2500k = 51.7 FPS, FX-6100 = 31.11; the FX-6100 has 60.17% performance of a Core i5-2500k.
Next up are application benchmarks. These type of benchmarks are basically dependent only on the CPU.
WinRAR is measured in total # of seconds to compress a file... so that means the lower the time, the better. Core i5-2500k = 191 seconds, FX-6100 = 242 seconds. This basically means that the FX-6100 has 78.93% performance of the Core i5-2500k.
Personally, I prefer the FLAC format compared to AAC format for lossless audio, however I am digressing from the topic... Again, the less time it takes to encode the better. Core i5-2500k = 141.4 seconds. FX-6100 = 235.8 seconds. That means the FX-6100 has 59.84% performance of the Core i5-2500k.
i5-2500k = 76.8 second, FX-6100 = 126.5 seconds. The FX-6100 has 60.71% of the Core i5-2500k's performance.
In this benchmark, the higher the score, the better. Core i5-2500k = 1.42, FX-6100 = 0.76. The FX-6100 has 53.52% performance of the Core i5-2500k.
Switching back to lower is better... Core i5-2500k = 237 seconds,FX-6100 = 360 seconds. FX-6100 has 65.83% the performance of the Core i5-2500k.
Switching back to higher is better... the Core i5-2550k manages 152.72 FPS compared to 99.29 FPS for the FX-6100 which results in 65.23% performance of the Core i5-2500k.
Based on whatever settings are used for encoding, the FPS drops sharply. The Core i5 got 29.59 FPS while the FX got 20 FPS. This means the FX-6100 only has 67.59% of the Core i5-2500k.
Keeping in line with higher is better, the Core i5-2500k scored 8.18 vs. 5.57 for the FX-6100. The FX-6100 manages 68.09% performance of the Core i5-2500k.
Core i5-2500k = 5.3, FX-6100 = 3.01. FX-6100 has 58.49% performance of the Core i5-2500k.
Finally, the last benchmark. This is taking longer to than I originally thought. Back to lower is better. Core i5-2500k = 46.57 seconds. FX-6100 = 70.5 seconds. The FX-6100 has 66.06% of the Core i5-2500k.