Most computer USB ports will only charge the iPad when the iPad screen is off, you won't be able to tell it's charging because as soon as you turn the screen on it will say "NOT CHARGING" this charge method is also a lot slower then the wall plug that comes with the iPad. If you have an ASUS motherboard tho there is a small utility out there made by asus called ai charge. Should be able to google asus ai charge. It will boost voltage to any plugged in apple device so iphone will charge at same speed as wall and iPad will charge normally. It's a little slower then the iPad wall plug but not by much, from what I've seen only an extra 30 min for a full charge at most.