Intel released the Core i5-9400F processor in early 2019 as a budget gaming CPU. The low price was thanks to the removal of all integrated graphics, which is a fine trade-off if you're going to be installing a dedicated graphics card anyway (and if you're serious about gaming, you should be). The CPU has already dropped in price a few times since its release, but now it has fallen to an all-time low of $119.99. That's $30 below the usual price, and $80 below the original MSRP.
The 9400F has six cores (no Hyper-Threading), a boost clockspeed of up to 4.10GHz and base clock of 2.9GHz, a TDP of 65W, and support for up to 128GB of memory. The 'F' means there's no integrated graphics support, so you absolutely need a dedicated GPU to get any kind of video output—just like with most of AMD's Ryzen processors.
Intel Core i5-9400F Processor | $119.99 (save $30)
One of Intel's budget Core i5 chips is at its lowest price ever. It's a great option for a mid-range gaming PC. You can also get the CPU from Best Buy.View Deal
It's worth noting that you can currently get a Ryzen 5 2600 processor for just a few bucks more. That CPU has twice as many threads as the 9400F, but the Intel chip comes out slightly ahead in gaming and other tasks that depend on strong single-threaded performance.
Just make sure to verify you have a compatible motherboard before buying. Any B360, H310, H370, Q370, Z370, or Z390 model should work.