Z590 Hero with 4 sticks of DIMM overclocking

[lawrencelyl]

I'm currently running 4 sticks of DIMM on Z590 Hero mobo. Found out that I can't overclock memory as high as before when I was running with only 2 sticks of DIMM.
Using 4x 16GB Hynix DJR chip.

With only 2x 16GB DIMM, easily run at 4000MHz @ 1.4V (18-22-22-42 timing).
Increase to 4x 16GB DIMM, have to drop speed to 3733MHz, else will fail Memtest64.

I tried increasing the timing and DIMM voltage but didn't help - still fail Memtest64.
Any suggestion what else I can try to make it stable with 4x 16GB at higher speed? Thanks.

[BigJohnny]

Running different kits I presume? Thats the problem. Often they wont run at all.

[lawrencelyl]

BigJohnny wrote:
Running different kits I presume? Thats the problem. Often they wont run at all.

Using 2 kits but same brand, same Hynix DJR chip. Even batch number also close to each other.
So I don’t think it’s the DIMM. Maybe this mobo need some tweaking to overclock higher with 4 sticks populated.Â*Â*

[Silent_Scone]

lawrencelyl wrote:
Using 2 kits but same brand, same Hynix DJR chip. Even batch number also close to each other.
So I don’t think it’s the DIMM. Maybe this mobo need some tweaking to overclock higher with 4 sticks populated.Â*Â*

Memory kits are binned in the density that they are sold in. Tune frequency, timings and voltage to accommodate. How much is needed depends on the amount of guardband put in place by the memory vendor. This is why mixing kits is ill advised.