screen resolution stuck at 640x480

[Metalrocks]

this morning my pc worked just fine. turned it off normally, then this afternoon i turned it back on again and for some reason i had no screen until it reached windows. but, for some reason its at 640x480 resolution and i cant change it at all. i have installed the drivers of my r9 290x GPU but this didnt work either. doesnt matter how many times i restart, turn it on and off, the resolution is fixed to 640 and no way of changing it. for some odd reason it also doesnt display my monitor (samsung S22C300, 22" screen). i have googled around on my tab (which im using now) but none of the options have worked like:
going under "config" uncheck base video under the boot tab. only that none of the boxes under that tab are checked.
installing drivers for my GPU.
pressing the AUTO button on my monitor.
holding down CTRL and roll the mouse wheel. but it did was change the icons on my desktop.

also plugging in my HDMI cable in to the MB didnt work either. it doesnt even have a pic. nothing.

none of them have worked at all. im out of options what i can do.
my MB is a asrock z97 killer fatality.

edit:
now i have no pic what so ever. either over my GPU or MB. have to hold the start button on my tower to turn it off. could it be that my GPU is screwed? its like having the same issue i had last week that my pc has no pic and i had to play around with the ram sticks to get my pc back running again. only there i believed it was the game that caused this issue in the first place. no screen, nothing. pc keeps turning it self on and off all the time. doesnt matter how many times i change the rams. everything is set to place. nothing is loose.
im out of options now.

 

[Metalrocks]

well, i brought my pc yesterday to the shop and today they told me that everything works fine. they had no issues to start up the computer and the resolution was at its normal 1920x1080. they have changed the ram after seeing that the pc did indeed keeps switching it self on and off again with no screen. this worked so far at the shop after several restarts to make sure things are working.so, i took my pc back home.
but what do i see again when i turn it on at home? its again on its fixed 640x480 resolution and i cant change a thing about it. cant even play any games since it complaints about the resolution or some its so stretched that i cant read anything.
so ram is not the issue, the monitor is 2 years old and my GPU is 1 year old. they used the same sized monitor as mine. only what they used is a ASUS wile mine is Samsung.

has really no one an answer to my dilemma? google so far could not answer my question and the shop was also a bit baffled when i have told them what my issue was.

 

[Niflhel]

Have you tried changing your resolution by doing this?
Right click screen > Screen Resolution > Advanced settings > List All Modes under the Adapter tab

 

[Metalrocks]

Have you tried changing your resolution by doing this?
Right click screen > Screen Resolution > Advanced settings > List All Modes under the Adapter tab

yep. nothing.
also, the problem is that the whole win is not available because part of it is hidden below the screen and i cant get up or minimize it.

edit:
looks like i have no screen what so ever. the monitor does not even show any reaction to my rig running. just a blank screen.

edit 2:
i tried by taking the GPU out and test it over the MB. the same result. no screen what so ever. but looks like my pc starts up normally. now i think that my monitor could be busted.

 

[Laughing Man]

1). Swap the HDMI cable with another one, or test the HDMI cable with another device (simple and cheap to fix)
2). Replace the HDMI cable and plug the computer in with a DVI cable (again simple and cheap it also tells you if it's the HDMI cable or the HDMI port that is broken)
3. Finally try the rig plugged in to another monitor or TV (tells you if it is your monitor that's broken or your rig)

yep. nothing.
also, the problem is that the whole win is not available because part of it is hidden below the screen and i cant get up or minimize it.

I am sticking with the it's the monitor, as the issue. The icons you can see on the desktop what size are they how big is the text is it the same size as when running at normal res? If the issue was with your computer resizing the resolution then the icons, text and other desktop objects would be resized to fit in to the new size, the fact that you have parts of the desktop missing suggests that your computer is running at the correct resolution and the monitor is not doing it's job correctly.

What model of monitor is it have you tried sourcing and installing the drivers for monitor (it's Samsung so good luck with that.)