[SOLVED] Can I flash my bios without purchasing a new compatible cpu?

Solution
The update came out nine months ago. So, it may already have the update. If it doesn't. Then you will need a compatible CPU or pay a shop to do it. It would be cheapest to get the lowest price compatible used CPU you could find on eBay. Then resell the CPU on eBay.
The update came out nine months ago. So, it may already have the update. If it doesn't. Then you will need a compatible CPU or pay a shop to do it. It would be cheapest to get the lowest price compatible used CPU you could find on eBay. Then resell the CPU on eBay.
 
Solution
Well eitherways you have to have a CPU in the board to upgrade the bios, or just borrow one from a friend of yours and update your bios, but there is always a risk here.
When i updated my motherboard bios my ram slots stopped working
until i down graded the bios to an older version so.
 
Well, its your choice, both of them are a good CPU's to be honest, and going with the i5-8400 will be less of an headache.
Though if i may ask will you be gaming? and if so what screen do you have?