Monitor Display Keeps Going Black

[JonnyAlpha]

Hi;

I have just finished a new build which for a week was working fine the all of a sudden the monitor keeps going black.

The only changes that took place around the time of the problem were installation of windows updates which included Service Pack 1 and the other possible culprit was trying to install Adobe Flash Player 11 which I needed to watch video demos of games in Steam, Adobe downloaded and installed but Steam Videos still didn't work.

I had also swapped the CPU which is an AMD A6 5400K which has a built in APU, although I'm sure that the display worked after this, in fact i'm sure it did.
 
The problem is I cannot pin down what caused the problem.

Monitor: Samsung S23B550VS 23 inch Widescreen LED Monitor, connected to onboard VGA - VGA
Mobo: ASRock FM2A75M-DGS
CPU: AMD A6 5400K
Mem: Crucial Ballistix DDR3 1866 2 x 4GB
PSU: Corsair CX500
Windows 7 64 Bit

[Geek-9pm]

When you power on the machine, What do you see?

[patio]

Also has another monitor been tried yet ? ?

[JonnyAlpha]

This monitor works on my FreeNAS box.

[patio]

Not what i asked...but OK.

[wafflingjclane]

It might be a problem with your graphics card I have tons of spare's laying around so I would just try a different one but if you don't try updating the drivers.

[Geek-9pm]

Also, if you suspect the OS is damaged, you can try to boot the machine with a 'Live CD" that automatically finds a suitable video driver.
On I  like  is Puppy Linux.
 It boots quick and does not require a working hard drive.
http://puppylinux.org/main/How%20to%20download%20Puppy.htm

[JonnyAlpha]

When you power on the machine, What do you see?

The PC boots normally ASRock Splash Screen with choice to boot into BIOS and boot options, then the "windows starting" splash screen then the "windows login" screen. Even at the "windows login" and possibly even at the "windows starting" the screen goes on and off!!

Also has another monitor been tried yet ? ?

Not tried another monitor yet but will do today I have a couple of displays with VGA inputs.

It might be a problem with your graphics card I have tons of spare's laying around so I would just try a different one but if you don't try updating the drivers.

   

No graphics card, I am using onboard gfx and the Radeon 7540HD GPU built into the AMD A6 Series CPU.

Also, if you suspect the OS is damaged, you can try to boot the machine with a 'Live CD" that automatically finds a suitable video driver.
On I  like  is Puppy Linux.
 It boots quick and does not require a working hard drive.
http://puppylinux.org/main/How%20to%20download%20Puppy.htm

I have a Linux live CD somewhere, I'll give that a bash, how can I determine whether the video output is coming from the onboard gfx or the built in GPU? 

[Salmon Trout]

how can I determine whether the video output is coming from the onboard gfx or the built in GPU?

Those are two names for the same thing.

[JonnyAlpha]

Those are two names for the same thing.

Uh? The onboard gfx I am referring to is the Radeon 7000 built into the ASRock mobo, the built in GPU that I am referring to is the Radeon 7450HD which is inside the AMD A6 5400K CPU. In my limited understanding (having never used the new A Series AMD CPUs) is that these are two discreet GPUs, one on the motherboard and one in the CPU which can both be linked (SLI??) together using AMD dual graphics capability.

 

[JonnyAlpha]

Plugged in a different monitor and into a different wall socket and the problem still persists, at least this rules out a problem with my brand new Samsung Syncmaster 23 Inch LED display.

I am now downloading the latest drivers for the mobo (All in 1 Drivers and VGA drivers).

[JonnyAlpha]

I have taken a short video clip of the monitor anyone know how I can upload it here? Also  anyone recommend a freebie app to test power supply? Maybe that's the fault?

[JonnyAlpha]

Update:

The problem seems to occur if I select a resolution above 1024 x 768, the native resolution for my Samsung Monitor is 1920 x 1080 so I am stuck with a crap resolution.

The monitor is listed as a Generic PnP Monitor in the Windows equivalent of Display Settings and in AMD's Graphics Control Engine, after installing drivers for the Samsng monitor i did managed to get Device manager to recognise the monitor by its correct name by Display Settings and AMD Graphics Control Engine still showed it a Generic PnP.

I have bunged in an old nVidia geforce 6600 Gfx card and have been happily working away all morning on this PC and monitor at a resolution of 1600 x 1200

Beilieving this to be a problem with the discreet GPU in the AMD A6 CPU I have RMA'd it, so lets hope that was the problem :-)

I am still a little unsure how to switch between the onboard GPU and the GPU in the CPU? In BIOS the only graphics options are Onboard / PCIe and PCI.