Question New RAM aint working.

Jan 24, 2021
Sooooo I bought new 3 HYPERX Fury ddr4 2400 Mhz 4GB sticks and since I have another 4 Gb same stick with the same specs I thought it would've been easy to just add in to make it quad channel. Apparently not.
Old ram boot:
Single channel: power on and runs through normally.
New ram boot on single and dual channel: powers on -> LED EZ debug switch lights on and flashes CPU and DRAM.

MSI B250 Mortar
GTX 1070 Mini
Gigabyte PSU - 1200W
NVME - 500 GB
Jan 24, 2021
Well when its single channel with the new ram and load into bios, it says "XMP not supported". Thought to myself if I got scammed.
First of all, your B250 motherboard only supports 2400 speed ram.
XMP may be available on better motherboards capable of overclocking.
2400 speed is fine for Intel since you have a discrete graphics card.

Intel is dual channel only, regardless if you have 2 or 4 sticks.

Ram is sold in kits for a reason.
A motherboard must manage all the ram using the same specs of voltage, cas and speed.
The internal workings are designed for the capacity of the kit.
Ram from the same vendor and part number can be made up of differing manufacturing components over time.
Some motherboards, can be very sensitive to this.
This is more difficult when more sticks are involved.

Your ram is not matched.
Most of the time, mismatched ram works, but apparently not in your case.
Return the ram you bought and buy a 2 x 8gb matched kit.
Keep the old ram as a spare or sell it.
4 sticks in a dual channel-only capable mainboard is not 'quad channel', it's just 4 sticks...

16 GB is plenty for gaming, return the 3 individual sticks if you can, and get a 16 GB kit , which is 2 x 8 GB sticks designed/certified/tested to work together