I've had clients bring me beepers and it was the HDD failing and not heat or BIOS. The G3 looks to be old but here's the service manual if you feel the beeps are from the speaker. look up the code.
https://www.google.com/search?client=opera&q=hp+probook+g3+service+manual
You can add which G3 it was to the serach.
Hey there. So my hp probook g3 is making beeping noises during startup. Sounds like 10 to 12 beeps. I have updated all the bios files . Did a system restore . Any help on how to fix this would be much appreciated. The laptop does start up and I am running Windows 7.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic