Question System Won't Boot with 4 RAM Slots Filled, Boots Fine with 2. All Sticks/Slots Tested Fine.

[koberulz]

ASUS PRIME B660M-A CSM DDR4, Intel Core i3 12100, G.Skill 16GB Kit (4x8GB) DDR4 Ripjaws 4 Red C15 2400MHz

I've tried each stick in each slot, and it boots to the BIOS just fine. Same with two sticks. But with four, the fans spin up and the power LED comes on, but the monitor acts as though nothing has happened.

 

[helpstar]

Check the pins of the CPU, any bent?
Check the Ram using a boot able USB thumb drive with memtest on it.
Update the Bios to the latest version

 

[Zerk2012]

ASUS PRIME B660M-A CSM DDR4, Intel Core i3 12100, G.Skill 16GB Kit (4x8GB) DDR4 Ripjaws 4 Red C15 2400MHz

I've tried each stick in each slot, and it boots to the BIOS just fine. Same with two sticks. But with four, the fans spin up and the power LED comes on, but the monitor acts as though nothing has happened.

So your using 2 different 2X8gb kits of memory instead of a 4X 8gb set sold in one package.

Install 2 sticks boot into BIOS, change the memory voltage from 1.2 to 1.3 volts. Shut down and install all 4 sticks.

If that works try lowering it to 1.25.

 

[koberulz]

I don't know how to adjust the voltage. I've looked through the manual, but unless they're calling it something else I can't find anything.

EDIT: Found the setting but it's stuck on Auto and isn't adjustable.

 

[koberulz]

Okay I obviously screwed something up because now it won't POST at all.

 

[koberulz]

CMOS reset, no change. Removed one of the two sticks. Boot. Swapped sticks. No boot.

So now I have a bad RAM stick.

 

[koberulz]

Okay, replaced the bad DIMM and it boots with all four at 1.3v.