Speakers make sound rigth after pc shut down

[themis]

I’ve had my pc for over 5 years with the following specs:

cpu: intel i7-4970k
gpu: gigabyte gtx960 4gb
motherboard: Gigabyte GA-Z97X-GAMING 5
ram: fury hyperx 8gb
sound card: creative sound blaster zxr

I recently replaced my gpu with a Gigabyte 2070 super and my psu with a Gigabyte P750GM. After that my speakers make a weird laser sound right after my pc is shut down. I have attached a file with the sound. The sound is not made when i restart my pc. Also the sound only comes from the sound blaster sound card not the motherboard integrated sound card. My speakers work perfectly fine and the sound is made with other speakers as well so the problem is on the pc. The sound is not made when i switch the output to my headphones. I changed my gpu back to the old one and the sound was still there so i think my psu is to blame.. Any help would be appreciated!

[veeg]

Hello

Hopefully some of our members will chime in soon..

@PeterOz

[Bruce]

I had a similar noise when shutting down one of my PC’s years ago.
it was just capacitors discharging after power was cut and causing electronic interference that the speaker circuity was picking up until it too completely lost power.

changing those two bits of hardware would be the cause, either they are pumping out more interference or unshielded cables are closer together.

[themis]

I had a similar noise when shutting down one of my PC’s years ago.
it was just capacitors discharging after power was cut and causing electronic interference that the speaker circuity was picking up until it too completely lost power.

changing those two bits of hardware would be the cause, either they are pumping out more interference or unshielded cables are closer together.

Thanks for the quick reply!
I am bummed because the psu is new and i dont know if it is defective. Whould it be worth it to use my warranty or do you think it is the models problem? Also i have no idea if this is harmful to my system.

[Bruce]

while I’m no expert in the field, I would be really surprised if it was in any way harmful.
and I base that theory on building PC’s since 1988 and being a hobby enthusiast with electronics since 1979.
as I said, mine did it for ages until I upgraded things and the noise went away.
I’m as certain as I can be that you are just witnessing the side effect of the internal electronics discharging and the sound system picking up that discharge.
you have upped your PSU wattage so more current is flowing around, add to that you would have unshielded wires close to the new hardware and things can be explained away very quickly.
it only happening when you shut the PC down also supports my theory - any electrical circuit suffers their biggest stress when turning on and shutting down. it’s one of the original theories why computers were left on 24/7, as mainframes still are.

try move any wire associated with the speakers as far as way as possible from anything else.
obvisously some things won’t be able to be moved, but see what can, and if it helps.

[themis]

I will be upgrading the rest of my pc components shortly so i hope the problem goes away for me too. Thanks a lot for your help!

[Bruce]

while I would like to say it should, and probably will, sadly only time will tell.
good luck with the rest of the upgrades.