Beyond a ~$500 price range, building it yourself is cheaper and offers better quality, but this is a brief guide for those who simply don’t want to invest a lot of time.

Recommended: Ryzen 3, Ryzen 5, Intel i5’s
Not Recommended: AMD FX (inefficient energy hog)
i7’s are great for high-end gaming (if you have a high Hz monitor)
Ryzen 7’s are great for video editing (but inferior to i7’s for high-end gaming)

Video Card
Currently, Nvidia’s GTX series offers better performance at each respective price point than AMD’s cards.  GTX 1050, 1050 Ti and 1060 are all good options.  However, I have seen a few pre-builts with AMD RX cards at a decent price.

8 GB is plenty.  16 GB will help video/photo editing but won’t make a noticeable difference for gaming.

Power Supply
For those who plan on upgrading the video card to a higher-end one down the road, you may want a computer with a 450-550+ watt power supply.

An SSD will massively improve the speed of your computer experience and builds with them are generally recommended.  Many builds under the $800 price point only come with a hard drive, but leave some room in your budget to add one in yourself.

Look for Sales
Shop around different stores and brands.  Oftentimes, you can get the PC for $50-100 cheaper which means you aren’t paying that much more to have the PC built for you.