Monitor doesn't recognise video card

[Vaio]

Hi guys, it's been 2 years since I bought my PC from PCspecialists and it's been running completely fine. However, recently when I turn my PC on for some reason my monitor acts as if the PC isn't on. I've opened the case to make sure nothing had come out of the slots and cleaned the inside.

This worked for a couple of days and now it's playing up again. I'm guessing it's a loose connection somewhere or my graphics card? I have a GTX 580 connected via DVI.
Sometimes when I do bang my PC the video will show up on my monitor??

Really confused as I don't know what it could be. It's definitely not my monitor as I use the HDMI connection with my mac.

 

[SpyderTracks]

May be worth taking out the graphics card and reseating it, and perhaps trying another cable.

 

[Vaio]

So I tried it with a HDMI cable and still no luck.

Resetting the PC a few times normally does the trick, so no idea what it could possibly be.
I will try taking the card out and putting it back in, although I have made sure it's already sitting properly.

 

[Lez501]

Have you tried cycling the monitor through it's various input modes i.e. HDMI --> DVD-i --> VGA etc.

I get this on very rare occasions with my iiyama monitor, and it fixes it.

 

[Vaio]

Have you tried cycling the monitor through it's various input modes i.e. HDMI --> DVD-i --> VGA etc.

I get this on very rare occasions with my iiyama monitor, and it fixes it.

Yup tried this too.

Normally my monitor will automatically connect to whichever input has connection but yeah, it just blinks to say show there's no input

 

[SpyderTracks]

Would be worth trying the monitor on another PC also, just to verify its not an issue with the monitor itself.