I am having this same exact issue with the same two components (DZ77GA-70K and i7 3770K). I see you posted this four days ago. Have you found an answer to this?
No,I have not. I am going to see if I can overclock the processor, up the v-core so that even if it drops, it will drop to a more respectable number than 1.5!
Hey are you aware that all processors since like the introduction of the core architecture all operate like this, by core i mean since the introduction of many core (2 cores and above). be it AMD or Intel they all operate in this manner.
So the thing is the processor you have is not faulty at all, 2nd & 3rd processors down clock to 1.5 while idle, simply put it will only run in specified speeds when a task/tasks needs that kind of muscle.
Truth is the CPU doesn't need to run in full speed consuming all that power all the time, you don't need full speed all the time to brows internet, watch a movie flipping photos this tasks can run on even 500MHz CPU or less
Simply put its a way of not wasting resources, why would a computer run at say 3.5GHz on 4cores/8threads while doing nothing its a total waste of muscle and power and the truth is only highly demanding tasks should make it run at such speeds not tasks that can be handled by Phones at less speed
I hope you do get my point
Your CPU is ok
With overclocking you can have a consistent clock frequency, even with the newer generations of CPUs. I had my old Q6600 running at a consistent 2.4, and my i7 920 at 2.6. I am not much one for overclocking, but I thought I'd give it a shot with my new build.
First, I would just like to get the CPU to remain at the same speed, and definitely not 1.5 or 1.6. I have disabled EIST and Turbo Boost, adjusted the maximum non-turbo ratio to 40 and left the host clock frequency at 100. Everything with the option is set for "Performance". I haven't messed with voltages yet. But, what's strange is that when I disable EIST or Turbo Bost, they both say by disabling one it will in turn disable the other. I haven't noticed this, and have had to manually disable both.
As it stands right now, I'm running my system with default settings with the exception of fan speeds & memory clocking. My RAM has a built-in XMP to get it up to 1600, so why not?
I'm honestly beginning to think this is an Intel issue pertaining the to DZ77GA-70K particularly. It is a rare thing to find any forums or threads out there since the release of these two components that pertain to them working together, and getting clock speeds where people want. The most common overclocking questions I have seen posted and/or answered pertain to the 3770K with an Asus board, MSI, Gigabyte, etc. Apparently, no one likes the board 'we' have, James.