Hi everyone,

My specs are:-
Windows 7 64bit
Core i5 2500k @4.5GHz @1.28v OC using offset voltage
Maximus v Formula/Thunder FX (currently on 1309 bios)
MSI 680gtx 2gb lightning (f7-f8 Ln2 Bios) these were one of the first 5000 cards released
Corsair vengeance 2x8gb 1600mhz 9-9-9-24-2T @1600mhz
BenQ 2420T 120hz Monitor (connected threw DVI lead)
EK H30 360 HFX watercooling kit (cpu and mobo vrms)

I need help in respect to this issue ive been having, some kind of conflict after i install Nvidia driver for my msi 680GTX Lightning upon restart right after the windows logo (4 colours coming together)
Straight after that where normally you should then see the welcome screen my screen goes black you hear the chime that youre entering desktop then it appears, sometimes at this point in which i have stated the monitor loses signal entirely and you see it go into standby then comes back on as you get onto the desktop. The time does vary abit when it goes black but normally around 5-8 seconds.

With the standard windows driver i see a welcome screen as normal and everything behaves normally. And if i boot into safe mode with or without driver installed (as no installed Nvidia driver gets loaded at this point regardless i see the welcome screen and everything behaves as normal.

Im at an end with this problem as im now on my 5th windows installation in 3 weeks i have been trying fixes and variants in order to try and identify what the issue could be.

When i was stability testing the system on the first install i done upon building it,
i was seeing while Intel burn test was running the Video driver would crash and recover with a kernal error (at the time thought it might have just got corupted from the occasional BSOD i got while testing the system to find my OC settings and a fresh OS install would fix it)

Here are all the things i have tried so far...

-ive ruled out the graphics card with a number of things ive tried nearly all the drivers available on the nvidia website, (clean install everytime driver sweeper etc.)
-Flashed both graphics card bios's with the ones found on msi's website stating "improved motherboard compatability" (these bioses where shipped with the later Lightning 680's with Nvidia's voltage lock implemented)
-Tried the graphics card in another machine (p67 chipset, i5 2500k) *Worked perfectly.
-Tried a Nvidia 470 in my system (Again Black screen as stated above after driver install)
-Removed Graphics card entirely and used onboard graphics from i5 using HDMI to monitor and sony TV (at seperate times) after installing the driver for the onboard graphics, black screen persists at welcome screen.
-Tried the system at stock speeds
-Used the 1408 Bios (both stock and OC)
-Booted with minimal services running
-Disabled onboard audio and Lan port
-Disabled HDMI audio found on the MSI 680gtx
-Tried connecting the monitor with HDMI as opposed to DVI
-One of the 5 windows installs i done i tried installing the Graphics card first as a test to see if perhaps chipset drivers or usb drivers, sata etc might have been conflicting but still black screened as mentioned above after installation of the video drivers

My conclusion is that there is some kind of hardware error upon the motherboard and is the motherboard which is at fault, i have now ordered a MSI z77 Mpower and should get it by friday as a test to see if such an issue is native to random z77 chipsets

As far as i have found all over the net its mostly asus motherboards that are having such issues in respect to black screen upon log on as ive already read the thread in this forum about a solution to disable onboard audio etc.

Also would like to state that the Thunder Fx mic barely works as alot of people have stated this, and that the onboard mic needs full volume and +20db at least to be heard..

Another thing this mobo does is occasionally it double posts at the "testing CMOS pre post stage" it hangs on this status shuts off then boots up as normal, in which i believe its to do with once you have OC the system and fiddled with its bios (it doesnt always do this id like to add)

My main problem is the black screen... Please Could an asus expert advise on what i should do next as the only thing i can think of is the board is defective and should be RMA'd for this fault to be reconstructed with a Nvidia video card and fresh driver installation... I feel that im just unlucky that this is happening with my particular board.. but as every pc owner knows is to be expected from time to time upon building a new system..

Any feedback on this matter would be greatly appreciated...