That's not just an ASRock feature (or a "feature" at all, really), but something that ALL non-K Sandy Bridge and Ivy Bridge i5's and i7's can do, and it's doable because of a thing known as "Limited" Unlocked.
It allows you to raise the Turbo multipliers by up to 4 bins (400Mhz) each.
So, that means for your 3550, you will be able to OC to exactly the same speeds as that illustration shows (4.1Ghz max with one core in use, 4.0 with two, 3.9 with three, and finally, 3.8 with all 4 cores in use).
You won't be able to do any better than that, though. No "magic" that the ASRock board has (it doesn't have any at all), will unlock the CPU to go any higher.
You could gain another 100-200Mhz by raising the BCLK, but that can cause a lot of problems and IS NOT recommended.