RAM Slots 3 and 4 Problems

What does CPUz memory tab show for Memory?

PRIME Z270-K | Motherboards | ASUS USA

4 x DIMM, Max. 64GB, DDR4 3866(O.C.)/3733(O.C.)/3600(O.C.)/3466(O.C.)/3400(O.C.)/3333(O.C.)/3300(O.C.)/3200(O.C.)/3000(O.C.)/2800(O.C.)/2666(O.C.)/2400(O.C.)/2133 MHz Non-ECC, Un-buffered Memory
Dual Channel Memory Architecture
Supports Intel® Extreme Memory Profile (XMP)
** Refer to www.asus.com for the Memory QVL (Qualified Vendors Lists).
* The maximum memory frequency supported varies by processor.

PRIME Z270-K Memory / Device Support | Motherboards | ASUS USA

I'd be inclined to check that your current RAM options are suitable for dual channel use with it's native clock speed.
It might be possible to tweak it in the BIOS if that is the problem, or maybe there is a firmware update with a fix if it's a known issue?

What are your DRAM settings in your BIOS?

Check in the BIOS that all the DIMMS are enabled. If the RAM should be Dual channel you would use the slots like shown before. If they are enabled, it can be a bent pin possibly on the CPU, or bad slots on the MB

Your welcome

AlanWade said:

Yep mine is much the same as your screenshot with the exception of CHA which is blank. I think its time to bite the bullet and upgrade all of it. Thanks for all your help I have learnt a lot.

Alan

Sorry to hear the bad news. Did you pull your CPU and check the pins? Could be a bent pin.