Without seeing either of them, a good assumption is that you are using a monitor with a newer DVI input as opposed to a VGA input. You can purchase an adapter to connect the monitor to the older computer.
It is almost certainly possible. The monitor should connect via either VGA (a large plug with three rows of pins) or DVI (an even larger plug with several rows of pins and one large flat pin). VGA plugs are often blue and DVI plugs are often white. Almost any computer will have a VGA out, many have DVI out. These are standard across all monitors and computers, regardless of manufacturer.
Replacing a computer monitor should take less than 10 minutes. First shut off the computer. Unscrew and unplug the (blue or white) video cable for the monitor from the back of the computer, and unplug the monitor power cable. Then remove the old monitor from the desk, replace with the new monitor, and plug it into the video and power plugs. Start your computer and once it has started, adjust the resolution and refresh rate to match the specifications for your monitor.
It should turn off automatically if you plug it into your computer and turn the computer on. If it doesn't, something is wrong. First thing to check is the plug that plugs into the computer for bent pins. Also check the other end of the cable that plugs into the back of the monitor. If the pins are not bent then you will likely need to take it to a shop for repair or replacement.
a monitor
It depends what type of adapter you need, although almost all plugs for a computer (besides monitor and power) are USB.
This generally means that the monitor section of the unit is not receiving a video signal - make sure the jumper between the two video plugs in place. On mine unfortunately it was a dead motherboard for the computer. The monitor section was working fine - just no signal from the motherboard.
You should have a TV and not a computer monitor. The best would be a wide screen LED LCD HDTV in 1080p and while some would say with 3D I am not one of them. You can also use any standard 480I TV that includes RCA A/V plugs
Hard Drive..!
difult monitor and external monitor Because you probably have the connection (and ability to operate) a second monitor built in to the laptop. Check the plugs on the side of the laptop, there is no doubt a plug for an additional monitor.
Buy an S-Video cable which will hopefully fit their PC graphics card. (Any info on their PC spec, especially graphics card would help). It basically looks like a mouse or keyboard socket and will be next to where the monitor cable plugs into.
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Any external device that plugs into your computer, such as a printer, modem, scanner, or tape drive.