I had to ask myself the same question a week ago, and this link answers it similarly to UnbekannterNr1: https://www.computerbase.de/forum...

The E is the more expensive (compared to F) and has the best voltage converters (possibly relevant for over-clocking), and in my case I was still interested in an optical audio output (Toslink): which only the E variant still has.

In the end, it's the small details that can be relevant.

...E is for Extreme, B I think for Basic and F a hunch.

First of all, the B650 is the predecessor, the B650E is the newer version of the same chipset with minor improvements. The B650E-F and B650E-E are basically almost identical, the -E has more PCIe 5.0 connectivity and also slightly better CPU power supply with more phases. I would recommend comparing the boards in detail, as the number of available PCI Express lanes is only possible with the -E, especially when using a PCIe 5.0 M.2 SSD in combination with another 4.0 M.2 SSD and a full 16 lanes on the first PCI Express slot. With the -F, the GPU would only have 8 lanes left. In reality, this makes little difference to performance, but if you want to use both anyway, you could go straight for the more expensive -E. The decision really depends on the later use. I would generally no longer recommend the B650-A, the B650E costs almost the same and offers more.