Resolution stuck at 1024x768

[ArthurMoraesF]

I have an nVidia GTX 560 paired with a S23A550H samsung monitor and my resolution when using an HDMI cable has been stuck at 1024x768 even though my monitor supports up to 1080p (and is working perfectly).
When I connect the monitor through a VGA cable + DVI adapter it unlocks all the resolutions for me to choose but then the image is bad due to the VGA cable.

Things I've done so far:
a) Completely re-installed Windows (updated from Windows 7 to Windows 10);
b) Installed monitor driver;
c) Updated Chipset drivers;
d) Different HDMI cables;
e) Changed the slot for the graphic card;
f) Tried changing resolution via registry (found the strings on my own, changed then and it was still 1024x768 after restarting);
g) Obviously updated and unistalled and re-installed nVidia drivers.
h) Also tried to create a customized resolution via nVidia control panel but it did not work.

It all started when I got an old 20" monitor to replace my now-fixed monitor. It defaulted to 1024, allowing me to change resolutions back to normal just once which is weird. Since then, even when plugging my newer monitor, the resolution has been stuck at 1024.
I'm thinking at this point it may be a graphic card issue but I'm completely lost. Any help would be appreciated.

 

[popatim]

What was broke on it that it needed fixing?

I'm wondering if your 1080 panel got replaced by a 768 one. 🙁

 

[ArthurMoraesF]

What was broke on it that it needed fixing?

I'm wondering if your 1080 panel got replaced by a 768 one. 🙁

I got the panel replaced, yes, but I'm sure at this point they gave me the right one.

I actually managed to fix it by using a software called CustomResolutionUtility which overrides my monitor's EDID (or so I was told) and enables me to change to 1080p.

I appreciate the help anyway, thanks.