Some time ago Asus (and other brands) made it possible to overclock cpu's on H97 boards.
Now is my question if it is still possible to overclock cpu's on those boards or has intel prevented that from happening?
You can overclock via software as long as your chip is a k series, but in the bios of most (if not all) asus h boards there is no readily available means of overclocking.
That is not true (AFAIK).
You indeed need an K processor for overclocking, but you need an special chipset for that (Z97,Z87, etc).
In the H97 some brands unlocked the boards and made overclocking possible.
Then I don't think that you should expect overclocking.
If you have a "K" CPU then just get a Z97 motherboard. They are better for overclocking, as H97 wouldn't overclock so well even if it still could as it is not designed for overclocking. The Z motherboards would just be better optimized for overclocking.