On an unlocked Phenom II CPU the CPU-NB and HTT frequencies can be adjusted independently but the HTT can never be a higher frequency than the CPU-NB.
The Hypertransport Link (HT or HTL), typically refers to the CPU core (aka FSB) connecting clock frequency, so it's easy to get these two terms confused. Changing the HTL frequency in a locked CPU does change the HTT, CPU-NB and RAM frequencies. Think of it as changing the Front Side Bus (FSB), of an older CPU as "HTL" replaced the FSB in newer AMD CPUs.
Changing the HTT frequency by multiplier or FSB is possible and useful. In overclocking each CPU can respond differently because you're trying to make them run beyond their rated frequency. What works for one CPU doesn't always work for another. A CPU overclocking tutorial gives you information on what has worked for many but it is only a reference as to what may or may not work for your CPU. You'll need to tweak and try to see what works best for your hardware.
Edited by AMD4ME - 5/4/12 at 7:38pm