|I suspect you have both PC's at home connecting to the internet through a SOHO router which in turn is connected to your ISP. If this is the case then there's really no way for your ISP to break it down to individual PC's. |
You might be able to monitor bandwidth usage on your side of the external connection using 3'd party monitoring software. You might have to install it on both PC's though in order to get an accurate accounting of each PC's usage.
Conversely, you could install it on one, get the total from the ISP's website and then subtract one PC's usage from the total leaving you the amount of usage of the second PC.