Question Why Channel A DIMMs turns off after OC

Jul 22, 2018
Hi! I have a problem with Memory Overclocking. my spec:
motherboard: ASUS A88X-PLUS
APU: A10-7860K
DIMM_A1: Kingmax 2GB 1333MHz
DIMM_A2: Hynix 2GB 1333MHz
DIMM_B1: Hynix 2GB 1333MHz
DIMM_B2: Empty

HDD: STM3500418AS Seagate 500GB 3.5" 7200rpm

All DIMMs work correctly and without problem when they configurated by MEM-OK function of motherboard. once I overclock them, Channel A DIMMs shown as system reserved in Task Manager. only 2GB usable ( I tried using 2DIMMs in channel B, and then it shows 2GB system reserved and 4GB usable) also when it happens, Channel A DIMMs temps are equal to room, and Channel B DIMM is around 35-40°c . BIOS shows 6144MB ram istalled correctly.
Third timings go wrong after Overclock applies. CHA drive strenghts are 0 but CHB timings are correct.
my Overclock profile was working correctly before I add that Kingmax memory. also this Memory shown as Undefined in Bios ( but it works correctly when I don't overclock )
I overclocked them to 2400MHz with a loose timing : 16-18-17-42-58 ( as IGPU extremely depends on memory speed ) and with a voltage of 1.61volts.
I just repeated it with this new DIMM. but what I said happened. what can I do? pls don't say don't Overclock your Memory 😐. bcuz I'm here to Overclock it. thank you for your helps 😊