Monitors not being detected after boot

[BamLib]

BIOS and powerup screens are visible but monitor does not display in Windows 7 (64 bit).

After power up screen and the windows logo screen were shown, the screen's would go black and the login sound would play

Firstly, checked that everything was plugged in, restarted the computer.

Secondly, thought it may be a driver issue.

Booted up in safe mode, uninstalled current driver for my AMD Radeon Gigabyte HD 6870, downloaded the latest (vga_driver_amd_vista(win7)_8.782whql) driver off AMD's website and installed it.

Rebooted, same problem, BIOS and powerup screens are visible but monitor does not display in Windows.

Booted back into safe mode, went into Device Manager, under display adapters I clicked my card and disabled (Also monitors weren't showing up in Device Manager), booted back into windows normally no black screen but still with display adapter disabled.

Main monitor running through DVI-I
Second monitor running through HDMI
Third monitor running through a mini DP to DVI-I adapter

This started when I was fiddling around with the Device Manager trying to make it so I didn't have to unplug my third monitor and plug it back in when ever the computer was powered down, so it would actually display instead of saying it was receiving no signal. That night before I went to sleep I disabled the third monitor in the Devices Manger and in CCC, when I woke the next day and booted my Computer the problems stated above occurred.

 

[BamLib]

I uninstalled CCC and installed the latest version of AMD vision Engine Controll Centre, now I can boot into windows fine with all two monitors working fine (the third needing to be disconnected then reconnected) for a few seconds until... the computer freezes becoming unresponsive, still displaying whatever was last on there.
How can I fix this?


In a separate and semi related issue, upon booting into windows it seems one of the three monitors will not pick up the signal (usually the mini DP but it can sometimes be either the DVI or HDMI although more commonly the DVI), this will usually require the monitor to be manually disconnected and reconnected.
What's going on??

 

[BamLib]

More information on the freezing: If I go into safe mode and then go into msconfig and disable all non Microsoft services and disable everything on start-up, the computer no longer freezes after a few seconds of being in windows.

However, a few seconds after logging in, the computer will become unresponsive.

 

[BamLib]

Also just before I turned off the computer, I also disabled the monitor in CCC (aswell as it already being disabled in Device Manager).

In case you're wondering, My Specs:
Mobo: Gigabyte ga-m720-us3
GPU: AMD Radeon Gigabyte HD 6870
CPU: AMD dual core 3.2ghz AM2
RAM: 2x Kingston DDR2 2G
OS: Windows 7 Ultimate 64bit
PSU: 430w Thermaltake

(Freezing is still occurring 3 to 5 seconds after logging in)

 

[BamLib]

Reinstalled windows, working as good as new, how ever "upon booting into windows it seems one of the three monitors will not pick up the signal (usually the mini DP but it can sometimes be either the DVI or HDMI although more commonly the DVI), this will usually require the monitor to be manually disconnected and reconnected.
What's going on?? "