Beep on Startup

I now get a loud single beep on startup of my new IMac. I put my own memory in it...OWC. The thing the Apple store said is that 1 beep on startup means the memory is not checking out and because its not Apple memory there is nothing they can do about it. In utilities, both Tech Tool and the Activity Monitor say my memory is fine. Now what do I do. Sould I just ignore the beep?...thanks.....also..could i just be holding the start button down to long...sometimes it doesnt do it is I just hold the button down 3-4 seconds

Press the button and release - no need to hold it down. In fact what may happen is holding the button down too long causes a second boot and a beep. Let's know how you go.

maybe

Maybe it was me...Im still used to pc's. I held the button to long and it beeped.
Just clicking it on and not holding it in...no beep. What a dummy

Nah you ain't no dummy! The only ones who do not make mistakes are the ones who do NOTHING!

En oy our iMac!