Power supply, video card or motherboard?

I have a question I hope I can get an answer to. My older computer had started to "freeze" and lock up. I moved the computer and went to hook it up and when I attached the monitor cable to the video card and it caused the monitor to go into "sleep" mode. My question is this a motherboard issue or a video card issue? I cannot give specs on the card and what type it is. I know its made by Nvidia, power supply is 350 watts and the motherboard is a ASUS. I really can't give you any more information. I did hook up the monitor to another computer and it works fine.

Any help would be kindly appreciated.

 

when you mention sleep mode, does this occur as soon as you start the machine or after your os has loaded

also is the tower still running (fans spinning etc) when the monitor shuts off?

you also mention lock-ups etc, as this is an old machine have you opened the case and cleaned out all the dust and made sure all fans are clean and working ....best way is to use a can of compressed air

when you moved the machine is it possible the graphic card could have come loose, double check everything is seated properly and all cables etc are fitted correctly

does this machine work with another monitor?

theres a few ideas to get you started, have a look and post back, but if your still having problems we will have to consider a possible hardware failure

 

Make sure the video card is still completely seated into it's socket and make sure your computer's motherboard isn't grounding to the case somewhere after being moved. Remove all other adapter cards and try another video card if you have one.

 

Thanks for the replies. I don't have another monitor to hook up the computer too. I turn the monitor on and as soon as it touches the outlet for the card the monitor goes into sleep as the ready light goes to the amber color.
I started the computer without the monitor,keyboard and mouse and heard no BIOS beeps.

 

How old is it?

 

Power supply about 3 years old. Rest of computer about 6 years old.

 

Ok, do you have integrated graphics or a card?

If you are sure all the drivers are up to date then I would be checking the graphics card first.

May need another pc to do this.

If they are integrated and its gone then it is a new mobo.

 

Then you don't have integrated video card. Could try try a new video card. If it is integrated, then it might autodetect the video card if that is the problem.

Also could check the monitor video cable for damage.

Can the monitor do a self test without hooking up to the computer?