[SOLVED] 3 sticks of RAM works but 4 wont POST

[dstephens20]

I recently purchased two new sticks of ram to bring my pc from 16GB to 32GB. I didn't realize at the time but what I had bought was 3200mhz and my old ram is 3000mhz. Everything Ive read says they will work fine together, but they will be limited to 3000mhz which is fine with me. The problem is that I can only install one of the new sticks of RAM. The old sticks are in the A2 and B2 DIMM slots. Ive tested all four sticks of RAM and they're good, all 4 slots work as well and when I insert a new stick into either the A1 or B1 slots the PC boots and the BIOS displays 24GB RAM 3000mhz, but when I put the 4th stick into the last slot my pc wont post.

PC Specs:
Intel Core i7-8700K 3.7 GHz 6-Core Processor
Asus PRIME Z370-A II ATX LGA1151 Motherboard
Corsair Vengeance LPX 16 GB (2 x 8 GB) DDR4-3200 CL16 Memory
Corsair Vengeance LPX 16 GB (2 x 8 GB) DDR4-3000 CL16 Memory
ASUS TUF Gaming NVIDIA GeForce RTX 3080 V2 OC Edition Graphics Card

Things Ive tried:
enabling/disabling XMP
Resetting BIOS to defaults
Resetting CMOS
Updating BIOS

 

[Ralston18]

This motherboard?

Asus PRIME Z370-A II ATX LGA1151

[Do verify that I found the applicable User Manual.]

Some motherboards require that the first physically installed RAM module be placed in a specific RAM slot.

That does not appear to be required and thus a possible concern with respect to your build.

Was the second pair of new ram sticks purchased as a matched kit or separate modules?

Try the RAM sticks one at a time then two at a time to determine if one of the sticks is faulty.

As I understand your post you have done most of that. Still give it all a second try in order to double check.

Just be methodical and try various combinations (as supported by the motherboard) to narrow the problem down to a specific stick, a specific slot, or (more complicated) a specific combination of sticks and slots.

If not successful, you may need return the second pair of RAM sticks and try another set,