Displays sometimes fail to get a signal at startup

[Proffit]

Hello

My computer has recently started to have a problem where sometimes/often when I boot it up, my displays aren't getting a signal. The computer is booting fine behind the black screens, I can log in to Windows and shut it off, and sounds are fine etc.
If I try to power the computer on and off a few times, I can get it working and everything will be fine from then on.

My recent hardware changes are a Dell u3011 30" monitor and another 6gb of memory (same brand as before). I now run 30" and a 26" dual view. Ran 26" and 22" dual view before.
I have tried just using the 26" alone and it didn't make any difference.

I'm having problems finding a reason for this behavior. I have run memtest, prime95, furmark and all are fine, no high temps, PSU seems cool (Corsair 750w). All the lights are fine aswell when it fails to give a signal. And as I said, as soon as I get it working, the computer works fine.

I have a i7 920 at 3.8ghz, gtx 295, 12 gb ddr3, ASUS p6t motherboard.

I sadly don't have a video card around to check if that's the problem so I don't wanna blindly replace it unless I'm sure it's to blame.

Anyone have any ideas on what I can try to fix this?

Thanks

 

[Chainzsaw]

Did you make sure the cables are properly connected on your LCD's? Nice and tight, as well as on your video cards?

How do you connect them anyways? DVI? HDMI? DP?

 

[Proffit]

Everything fits fine. I have a single link DVI for the 26" and dual link DVI for the 30".
It's just so random since when it does work, everything seems fine. All it needs is that first spark.

 

[Chainzsaw]

Odd. Can you try different cables?

 

[Proffit]

Don't really have another set of dual link cables, and the problem occurred even when I tried running the monitors one by one. Both cables being faulty would seem very unlikely.