That's normal, that is the standby power light [aka Flea Power] and indicates that the motherboard has some power reaching it.
To turn the light off, power the computer off, remove the power cord from the power supply and hold the power button in for about 15/20 seconds, but when the computer is booted up, the light will again be lite.
If my answer was helpful, please use the 'Did this answer the question' and click: YesForum Member since 2001I am not employed by Dell
Thanks Bev! I was hoping it was a normal light and not a problem starting!
You are welcome and I'm happy to have helped.