SeaSonic 500W Bronze PSU (don't have the exact model on hand) Rynon X, PBO Enabled, no other BIOS tweaks doneĤx4GB Corsair ValueRAM 2400MHz (DOCP/XMP disabled)

Specs of the PC in question are as follows: Open to any feedback and suggestions on how I might solve this issue, thank you in advance. Booting into windows and checking task manager with 2 modules yields roughly the same amount of memory used as well. What I also found suspicious is that when booting into Windows and getting into task manager with 4 modules, it only shows 1.5GB of RAM in use after startup, which is suspiciously low imo. Could it be that one stick is 'bad'? Or that this 4x4 mix and match configuration doesnt work, despite the fact that the modules are, for all intents and purposes, identical to each other?

They are the exact same model with the same frequencies, latencies and voltages across the board. My main suspicion therefore is the memory, since it is not a 4x4GB kit, but rather 4 sticks of the same memory modules (essentially 4 'kits' of 1 stick each). The CPU works completely fine and functions as expected when stresstested (Cinebench R20 on loop), same goes for the GPU (Unigine Heaven on loop). Populating all 4 slots causes the system to stutter, freeze, video output to cut in and out intermittently, and usually ends in the PC just restarting itself (I'm assuming it BSODs, however I cant verify this, since it happens when the video cuts out, and the next time I get video out, it shows the system at the motherboard splash screen). I recently assembled a PC at work, and it's been incredibly unhappy when I fill all 4 DIMM slots with memory modules.

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