Something seems to be loose in my computer. The screen, often, turns pink, which is also darker and harder to see. If I squeeze the tower, on top, push my foot against the bottom, or even push the face of the tower, it goes back to white. But sometimes I have to repeat this several times until it stops getting pink again. Then I have to be really careful not to touch the tower, or step near it or else it will go back to pink.
What is loose, why does this happen, and how can I fix or tighten whatever is loose?
Actually, assuming it’s a PC, the first thing I’d do is to check the cable between the monitor and the PC - if that is securely connected, the next thing is to reseat the graphics card, like this:
Turn it off and disconnect the mains power cable.
Open the case.
Lay the machine on its side so that you can look down on the main board inside.
Locate the graphics card - trace the cable that goes into the monitor back to the computer - the other end will be plugged into a ‘D’ shaped connector mounted in a metal plate on the end of the graphics card.
Disconnect the monitor cable from the card.
Unscrew and remove the small screw securing the graphics card backplate to the chassis.
Place one hand on the metal chassis of the computer, with the other hand, gently ease the card out of the slot (make sure you’re not pulling it by anything that looks like it might snap off).
If there’s a lot of accumulated dust and fluff inside the case, now might be a good time to remove it, ideally with a can of compressed air (vacuum cleaners can create static discharges that could destroy components).
Gently push the card back into its slot, make sure that it goes all the way down, all the way along its length.
Replace the retaining screw (be careful not to drop it inside the case)
If the “pink” is sort of a magenta colour, then yeah, it sounds like you’ve got a bad monitor cable: somewhere in the cable (probably in the plug), the signal for the green part of the picture is being interrupted. Check to make sure that the pins in the plugs aren’t obviously bent or loose, or borrow a monitor cable that you know is good and try it out on your machine.
Just the other day I had almost exactly the same problem - all the stuff on my montior was purplish. Turns out the cat knock the montior cord that connects to the computer loose, and only some of the pins were in contact with the video card. This is probably what is happening with your machine, especially since you mentioned the problem fixes when you press on the tower. Unplug the montior from the computer, and plug it back again.
Further to what MikeS said, do green objects on the screen actually disappearor darken when everything goes pink? - THIS text should go black and THIS text should turn dark blue and THIS text should be unaffected, if the failure is in the green channel cabling.
This is most likely a cable problem. Either the cable is broken or there’s a bent or loose pin at one end. Check that it’s properly connected at both ends.