Why I Love Yellow USB Ports (Sleep and Charge) Josh Smith07/23/2011 This week I have been working in all kinds of places, which means I am spending more time than normal on my ThunderBolt, which translates into horrible battery life. Thankfully the little yellow USB ports on several review notebooks have saved the day. The yellow USB port is becoming fairly common on new computers. It signifies a sleep and charge port, which will use your notebook’s battery to charge your smartphone or other similar size gadget while your notebook is closed and off.Advertisement While I can’t count on being near an outlet or car charger for more than a few minutes I have a notebook nearby all the time. This lets me save notebook power while charging up my devices and allows me to charge while the notebook is in a bag. Yellow USB Port - Sleep and Charge Many of the notebooks we review have sleep and charge ports on them. You can normally spot them with the telltale yellow inside, but occasionally the ports will be a standard black with a small charging symbol next to them.Advertisement The MacBook Air doesn’t have a a sleep and charge port, but it will charge a phone while closed and asleep. I have found that the USB port closest to the power connection is the most reliable. On the Air, you need to turn the computer on, plug in your phone and then close the notebook.Advertisement Up until recently I wasn’t too big on these ports, but over the past week they have saved by battery on more than one occasion, allowing me to tap into my MacBook Air’s long lasting battery to charge my ThunderBolt while I wasn’t near an outlet or didn’t have a traditional USB charger. You have to give up some notebook battery life when you use the Sleep and Charge port, but with 5 hour and up notebook batteries these days, it is handy to have access to a quick charge like this.