I don't mean actual speaker, there's a mini-speaker meant for alerts only connected in the small pins at the bottom left of the motherboard (next to the regulatory capacitors at the corner, usually just a tiny one about half a cm big hanging there but on older computers it used to be much bigger and mounted on the case itself on stock builds). Anyway, does the computer appear to be running if you leave it be? If not getting a display, but is running, then leave speakers on, if it boots into the OS and you hear the startup sound, then the PSU doesn't give enough power to your GPU, meaning faulty PSU. If it just runs, leave the case open and then look at the fans. If they are all spinning at proper speeds (hard to know without experience, but try to tell), then it means it's booted into the BIOS due to part failure. If the fans don't spin as they should (during startup fans always spin at full speed until BIOS settings are loaded so you should be able to take your time and see), then it's a faulty PSU for sure (usually it's the CPU fan spinning for a bit, stopping or heavily slowing down and starting again). That last one is the easiest way to tell if PSU needs replacing. Finally, if you can tell me exactly which pin it is, then I can tell you if it matters or not. Hold the connector facing towards you, with the 4 part being on the top, then tell me which side and which pin it is from the bottom upwards. Also, check if your old PSU was missing a pin or not there. SOME PSUs instead of having one cable go in each pin, have two cables go in the same pin leaving one pin unattached, EVGA does that often, so make sure that's not the case and we are looking into the wrong issue too