Converting a VGA signal to USB power is impossible. A device using a VGA signal is outputting a graphics signal. A USB transmits, or stores data and cannot process a graphics signal. An adapter and the software driver that comes with it can turn a USB port, or device, into a VGA compatible device. For example, sometimes a computer program, such as a game, requires the use of more than one monitor. A computer only has one VGA input area. Because the monitor uses a VGA connection, it cannot plug into a USB port, necessitating the converter.
VGA stands for Video Graphics Array. A device using VGA signal uses a specific VGA cable connection. The VGA connection consists of 14 or 15 18 gauge wires wrapped in rubber to form the VGA cable. The cable has connections on each end consisting of 15 pins each. The pin connector plugs into the VGA display (the monitor) and then attaches to the VGA output (the computer).
USB is short for Universal Serial Bus. It is considered a universal connection device. Typically, most modern devices that connect to a computer use this type of connection. It is used to connect devices together and transfer information form one device to another. Like a computer connecting to a peripheral device. A peripheral device is anything that connects to the computer using the USB port connection to do so. The devices connect to the computer using a USB cable, connected to a small connection head. It is much smaller than that of a VGA connection. The area on the device to connect the USB cable to is a port. Each port needs its own driver, or software full of instructions, telling the port what to do with the information that comes through it.
Purchase an adapter device (converter) from any electronics store. It comes with the needed software drivers in the package. Open the package and insert the software disk into the CD drive. In Windows XP, if Autorun does not open the disk to view the files automatically, do so manually. Click "Start" then click on "My Computer" in the right pane. When "My Computer opens," double click on the CD drive to start running the software and install the drivers for the adapter. When it runs, the "Installation Wizard" appears. In Windows Vista, the Autorun feature will open the Installation Wizard automatically. Install the software according to the Wizard by following the prompts. When the Wizard asks you to, plug in the VGA converter to the USB port on the computer. The location of the USB port depends on the make and model of the computer itself. Consult the computer's manual for its location. The software then finishes installing. The adapter is ready to use and you can now connect the VGA device to the adapter and use it as normal. This will need to be repeated on each USB port you want to use the adapter with. Instructions for installing the converter on a Mac computer vary depending on the machine used. Consult your Mac's manual for instructions.