MacBook Air 2011 3 beeps, black screen

I have a 2011 MacBook Air that was working great until yesterday. I came back to find a black screen and 3 beeps followed by a 5 second pause followed by 3 more beeps. This pattern continues. I have to hold the power button for about 10 seconds to make the beeping stop. I have tried all the multi key reset/diagnostic alternatives I found online, nothing worked. Suggestions?

Thanks,

Rich