No - you need to use the same spec.
Normally if it's a memory problem then you wouldn't get anything, but have you tried the RAM module in any of the other slots ?
It's generally best to use two modules and then you can use both channels and that gives you option of checking each stick because one can pull the other down.
If you remove the module and boot, you should get the memory error beeps but if you don't then that tends to point to the motherboard.
Tell-tale signs on the board can be swollen capacitor cans, but they aren't always the problem.
When you remove the RAM module, check to see if the pins are clean - they can be cleaned gently with an eraser and any residue brushed away - also check the condition of the graphics card and reseat.
EDIT - It looks like it's quite involved to check the PSU -
https://www.lifewire.com/how-to-manually-test-a-power-supply-with-a-multimeter-2626158
