Video card OR cable OR?? Monitor sleeping

I am trying to find out what is wrong with fiance"s desktop
It"s a HP Pavillion a6300f Vista and has a dual core Pentium
The monitor simply says no VGA Input then says Monitor going to sleep
Then the monitor turns off
I have tried another cable (not new one) and have checked all the connections multiple times. What do you think? This system has seen little actual use although she leaves it on almost all the time.

 

Is the system itself running?
Have you tried a DVI cable instead of VGA?

Are your graphics onboard or PCI/e/AGP?

Does the monitor have settings/options to use different cables (VGA/DVI/HDMI) and if so make sure it is set to the correct setting for the cable you are using.

Edit: Also, have you/can you try a different monitor?

 

System is running.
Haven't tried a DVI cable. I think there is an option on the monitor for different cables. No second monitor to try there. I think the graphics are onboard integrated.
I will check monitor for which cable setting. It is a HP monitor that came with the desktop I think. If the cable option is set for VGA, which do you think would be more cost effective: Get a new VGA or a new DVI cable?

 

Oh I wouldn't buy anything until we can diagnose the problem.

One other thing you could try is hooking the monitor up to another PC if possible.

 

Thanks I hadn't thought of that.
One more question:
If the monitor displays the msg VGA no input, then monitor going to sleep, could it still do that if the video card was bad?

 

Yes, quite possibly.

Unusual in my experience for a video card to just fail like that though, usually you get some form of warning signs first, but yes that is a possibility.

 

Maybe cable as first choice right now?

 

Diagnosis is the best way, but I would try and borrow a cable rather than buy one, or buy one on the notion you can return it should it make no difference.

Try as much of the above as you can and post your findings.

Also if possible try a video card in the machine, maybe you know someone or your local pc shop will have an old one you can just test with.
You will need a PCI-Express X16 card.

Here is all the information you may need about your machine.

http://reviews.cnet.com/1707-3118_7-32795310.html