When it was discovered that all of Intel’s 6th Gen (Skylake) Core processors could be overclocked using simple base clock adjustments, we were told by Asrock that it might be possible to overclock these processors using other motherboard chipsets besides Z170. Super Micro has had an H170 motherboard on the market for several weeks now that is capable of performing base clock overclocks, and Asrock announced at CES that it will have four motherboards capable of this feat, as well.
Although increasing the clock speed on the processor should increase its performance, there are some serious problems that come from enabling overclocking with non-Z170 chipsets, and users will need to carefully weigh the pros and cons of these motherboards before buying.
Modding A Chipset To OC
With the exception of the Z170 PCH, chipsets created by Intel for the LGA1151 socket often don’t give users voltage control of several key pieces of hardware, such as the CPU, and lack several other overclocking-related features such as multiplier control, base clock control, Vdroop, load-line calibration and others. This is partially because these features are not supported on non-overclocking chipsets by design, but it’s mostly because many of these features aren’t particularly useful if you can’t overclock, so motherboard OEMs don't waste their resources implementing them.
In order to enable overclocking on a chipset like H170 or B150, hardware modifications and firmware support for these features must be added. Motherboard OEMs can make these changes, but it has the side effect of disabling several other features. Asus, Asrock and MSI told us that non-Z170 chipsets modified to enable overclocking will lose Hyper-Threading support and will be unable to use C-states to reduce voltage and power consumption when the system is idling.
Because motherboards using these modified chipsets are focused on overclocking, losing the ability to use C-states isn't a major issue, as overclockers often disable power saving features in order to obtain higher overclocks. Losing Hyper-Threading support, however, is a huge problem, as Core i3, Core i7 and Hyper-Threaded Xeon CPUs will lose a significant amount of performance in multi-threaded workloads, which defeats the purpose of overclocking in the first place.
Taking these problems into consideration, motherboard OEMs have responded differently to the idea of developing non-Z170 overclocking motherboards. Before we go over how the various OEMs are reacting to this concept, there are a few important points that need made.
First, the H170, H110, B150, Q170, Q150, C232 and C236 chipsets have Hyper-Threading and C-state support, but the hardware alterations required to give them overclocking features permanently disable Hyper-Threading and C-states regardless if you are actually overclocking or not, and it doesn’t matter which CPU you use.
So, if you aren't going to overclock, you will want to choose a different motherboard with a non-modified chipset. Second, although modified chipsets capable of overclocking will lose these features, it is an issue with the motherboard and not the CPU. Non-K CPUs overclocked with a Z170 chipset motherboard will still have full support for C-states and Hyper-Threading.
In addition to the problems mentioned above, Asus stated that motherboards using modified chipsets to enable overclocking will also lose support for some instruction sets, and any non-Z170 boards designed to overclock would have significant reliability issues, resulting in numerous CPU and motherboard failures.
An Asus representative told us that to develop and sell these motherboards to its users would therefore damage its standing among PC enthusiasts. Asus made it clear that it felt producing motherboards with modified chipsets would be a huge liability, and that it would be irresponsible and a disservice to its loyal customers. Suffice it to say that you should not expect to see any motherboards designed to overclock from Asus on the LGA1151 socket with the exception of the enthusiast Z170-chipset boards.
Asrock took the opposite approach by already announcing two H170 motherboards, one B150 motherboard and one C232 chipset motherboard with overclocking features. Asrock said that these systems would lose support only for Turbo Boost and C-states, and although it was unable to resolve these issues, Asrock felt that it should release these motherboards because customers want them.
Gigabyte didn't have much to say on this topic, and it did not say if it would release motherboards with these modified chipsets or not.
When we asked MSI about developing non-Z170 overclocking motherboards, the company expressed concern about the reliability and loss of features that comes with modifying those chipsets. The company said that it doesn't have any current plans to release motherboards with overclocking features outside of its Z170 chipset systems, but it is currently testing the idea and might release some non-Z170 motherboards designed to overclock if it sees strong demand from consumers.
Super Micro Has An Edge
Unlike the other motherboard OEMs we spoke to, Super Micro discovered a way to enable overclocking on an H170 chipset without losing Hyper-Threading support. Super Micro said it was actually the first motherboard OEM to develop a motherboard with a non-Z170 chipset capable of overclocking Skylake CPUs. Its C7H170-M H170 motherboard has been available on the market for roughly three weeks now.
The C7H170-M is priced comparably to Z170 motherboards, but it proves that overclocking Hyper-Threaded CPUs on an H170 motherboard is possible without losing the extra CPU threads, and we will likely see more of these boards from Super Micro in the future. The system still loses support for C-states, but as we stated above, many enthusiasts will consider this an an acceptable loss, as they would disable power saving features anyway.
Choose Your Motherboard Carefully
Because hardware modifications are required to enable overclocking on non-Z170 chipsets, unless a motherboard OEM explicitly states that the system has this feature, you should not expect overclocking capabilities on non-Z170 chipsets. If you are set on overclocking and don't want a Z170 chipset, make sure that you choose your next motherboard carefully, as pairing the wrong motherboard and CPU together may turn your $300 Core i7 into a $200 Core i5 and significantly reduce your overall system performance.
Update, 1/13/16, 10:45am PT: There was a miscommunication between us and Asrock about what was disabled on its non-Z170 motherboards with overclocking features, and we have posted a new article covering these boards.