Whine in Chevy Cavalier

I have a 2000 Chevy Cavalier and the engine has recently been making a whining noise. The whine is low and intermittent; sometimes I can hear it when I’m accelerating (especially around 40 mph), othertimes I will hear it when I take my foot off the gas and am coasting. It doesn’t seem to get louder when I turn the steering wheel. I also hear it whether the car is cold or warm. Any ideas? I had the serpentine belt replaced within the last few months.

Have you opened the hood to see if you can detect the location of the sound while the engine is running?

It seems like it is on the driver’s side, but it’s hard to tell.