HELP!!! blank screen after boot

[compwizpro]

I have a HIS radeon hd 4890, evga 750i ftw sli, q6600 2.4ghz, ultra 650w psu and 4gb ocz sli ready ddr2 800mhz ram. Starting today, whenever I boot my computer, the windows 7 splash screen appears then goes away leaving my monitor with a blank screen(but is still on indicated by the green led instead of amber). Then the logging on screen appears for about 6 seconds and then after that blank screen but still green led which as far as I know means the video card is still supplying the monitor with a signal.

I am able to remote desktop into the machine and get a screen on the remote computer and am able to run all programs normally from there. Whenever I remote into the computer, the monitor comes back on with the logon screen for about 6 seconds and then goes back to blank with green led. If I am quick enough, I am able to log back in and use the computer for about 6 seconds before the screen goes blank again. It even happens when I go into the BIOS and after about 6 seconds in there, the screen goes blank.

I've tried resetting the bios, reseating and replacing the video card with an evga gtx 210 and same thing happens. Tried different pci-e slots as well.

Im leaning towards a bad mobo but is really strange as I am able to operate the computer just fine while remoting in through remote desktop from another machine.

Let me know what you think.

Thanks in advance.