Each CPU & Motherboard combination will be different on the speed you can reach even when using the same Model CPU & Motherboard. Some of mine will run 3.6, some 3.5 some 3.4 & some a low as 2.98 only.

The revision of the CPU & Motherboard cam make a difference even, you may simply have to run a little lower in order to run stable or lower your temps if your unhappy with what it's running at now.