I recently bought Ryzen 5 2600x along with ASUS Prime B370M-A motherboard.
The RAM are GSkill RIPJAWS 2x4GB DDR4 2400MHz
after assembling everything, there was no display on my screen.
the motherboard speaker had 1 long beep and 3 short beeps.
after searching on the internet, I found out that Ryzen doesn't supports on-board graphics.
My question is do I need to buy a discrete graphics card as mentioned on the processor box or upgrade my MoBo BIOS?
If upgrading BIOS will help, is there a way to do it without the processor ?
The Ryzen 5 2600x does not have a built in igpu, so yes, you would need a separate discrete GPU.
There is no Prime B370M-A motherboard so I am guessing you are using a Prime B350M-A.
If this is the motherboard you are using it needs to be on BIOS version 3904 or newer.
If it does need to be updated you can send it/take it to the retailer you purchased it from, take it to a local repair shop or get the "boot kit" from AMD.