Welcome to the forums!
No, nothing in the BIOS needs to be changed when you remove a stick of RAM.
It may be more beneficial to begin by testing both sticks with
Memtest.
If you get any errors during testing, then would be the time to test the sticks individually.
Perhaps you could post more information on your issues.
Have you recently changed any hardware or installed any new software?
Does your system BSOD completly randomly or is it generally happening when you do something specific?
Is anything overclocked?
How hot is your system running (use
Coretemp or
Realtemp for the CPU and
GPUz for the GPU) and have you cleaned the dust out lately?
Have you run an antivirus sweep lately?
What PSU are you using (brand, model, wattage, +12v amperage)?
Any odd noises or other issues with the system lately?