Best if very subjective, especially with motherboards because your needs can vary a lot.
The most important thing is you will want a Z97 chipset board, I would not look at anything else for that CPU and budget.
After that, the difference in boards is just going to be size (ATX, mATX, micro-ITX) ports and expansion slots.
Can you give any more details like what size board you want or what case you plan on using. Are you getting more than one graphics card? If so, AMD or nVIDIA and how many. Do you have any expansion cards already or that you will need. Some boards have legacy PCI slots and some don't. Do you need anything special like Thunderbolt?