Although Intel's CPU ratio overclocking potential of the new Haswell chips has been officially limited to the Z87-based motherboards with a Haswell "K" processor onboard, it seems that some H87 motherboards are also allowing you to boost the clock of your CPU.
According to Intel, the full overclocking capabilities (Base Clock frequency multipliers: 125MHz and 167MHz; fine grain base clock; unlocked CPU ratios and; unlocked memory) of the Haswell "K" SKUs require the use of a Z87 (Lynx Point) motherboard. The remaining H,B and Q87 chipsets are only offering unlocked processor graphics adn unlocked power.
However, Tom's Hardware
claims that there is a BIOS option called "Non-Z OC" in ASRock's H87 Performance motherboard, which suggests Intel might have "forgotten" to turn unlocked ratios off in one of its lower-end platforms. This could allow you to drop a K-series CPU into the specific $105 motherboard and overclock it using the processor?s ratio multipliers. The cost savings compared to Z87 would be significant.
The ovreclocking capability is currently available in the particular ASRock mainboard and an Intel Core i7-4770K processor. And of course, Asrock?s "non-Z OC" feature does not unlock multipliers on non-K Haswell CPUs.
What's left to see is whether other motherboard vendors will come out with enthusiast-oriented boards centering on H87 Express.