How do i tell if its my video card or my moniter going out?

everytime i attempt to go on the internet(have dsl) my moniter shuts off.its kinda of an old moniter,but someone told me its my video card please help?|||It only shuts off when you get on the internet??? When did the problem start happening. You can update your video card driver by going to My Computer and right click on it. Then go to properties, then Device Drivers and find your video card driver. Update the driver. But first I would turn my system off completely. Then power it back on and tap 1-2 times gently the F8 key. This should take you to the Windows Advanced Options Menu. Go to Safe Mode with Networking. Choose your Operating System. Then you will see a lot of file like lines just give it a minute to load. Then your screen will tell you to log in and log in. Your computer will be running is safe mode. Try the internet there and if it shuts down or off then that will tell you what it is. It would be convenient if you had access to another monitor then that will tell you whether it is your monitor or not. I find it strange that the video works but when you get on the internet it doesn't. So if it stays on in safe mode that means it is a software issue and then I would proceed to the update video driver step which can be done in safe mode or in regular mode. If the problem just started recently you can do a system restore and see does that help. You could have downloaded something from the internet that is messing with your system. Hope that helped.|||1 hook annother momiter to your pc

2 take it to the shop and have them do it|||u remove vdo card & connect monitor direct to mother board. if it shuts off it is due to monitor. if not its due to ur vdo card