Question PC no display and no hard drive activity light

[Toa]

So 3 years ago I built a PC. Upgraded my Power Supply recently and noticed my computer seemed to be running slower. Went to check the issue and the pc said only 4 (of my 8 total) gb was installed. No biggie. I reseat both sticks and then my PC proceeds to periodically turn on and then turn off. 3 years ago when I built the PC I for some reason didn't install anything to give me beep codes (I just ordered some to install), but I suspect it's likely the ram since that was giving me issues in the first place, and that's all I messed with. But the plot thickens. I take out my graphics card, nothing changes when I boot. I put my card back in, suddenly the system runs continuously and doesn't shut down by itself. I have no idea why. But nothing displays, no POST, no HDD light (and just to ensure I did try both the on-board hdmi and the hdmi port on my graphics card). Nothing different happens when I unplug all components from the power supply save for the CPU and Mobo. I have ordered new ram, and hopefully that fixes the issue. But if this doesn't fix the issue, does anyone know what problem this may sound like?

 

[rgd1101]

full system spec? include make and model of the psu